为研究胰腺分泌活动的调节机制，研究人员对实验动物做了下列实验。 <table style="BORDER-COLLAPSE: collapse; MARGIN-LEFT: 26.75pt; mso-padding-alt: 0cm 0cm 0cm 0cm; mso-table-layout-alt: fixed" border="0" cellspacing="0" cellpadding="0" _dj="MsoNormalTable"><tbody><tr style="HEIGHT: 19.2pt; mso-yfti-irow: 0; mso-yfti-firstrow: yes"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1.5pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 47.25pt; PADDING-RIGHT: 0cm; HEIGHT: 19.2pt; BORDER-TOP: windowtext 1.5pt solid; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm" valign="top" width="63">  实验</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 234.25pt; PADDING-RIGHT: 0cm; HEIGHT: 19.2pt; BORDER-TOP: windowtext 1.5pt solid; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt" valign="top" width="312">    处理方法</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 69.1pt; PADDING-RIGHT: 0cm; HEIGHT: 19.2pt; BORDER-TOP: windowtext 1.5pt solid; BORDER-RIGHT: windowtext 1.5pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt" valign="top" width="92">  胰液分泌量</td></tr><tr style="HEIGHT: 19.9pt; mso-yfti-irow: 1"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1.5pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 47.25pt; PADDING-RIGHT: 0cm; HEIGHT: 19.9pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="63">    ①</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 234.25pt; PADDING-RIGHT: 0cm; HEIGHT: 19.9pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="312">用适宜的电流刺激通向胰腺的神经</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 69.1pt; PADDING-RIGHT: 0cm; HEIGHT: 19.9pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1.5pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="92">    增加</td></tr><tr style="HEIGHT: 19.9pt; mso-yfti-irow: 2"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1.5pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 47.25pt; PADDING-RIGHT: 0cm; HEIGHT: 19.9pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="63">    ②</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 234.25pt; PADDING-RIGHT: 0cm; HEIGHT: 19.9pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="312">切断通向胰腺的所有神经，当食物经胃进入十二指肠中</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 69.1pt; PADDING-RIGHT: 0cm; HEIGHT: 19.9pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1.5pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="92">    增加</td></tr><tr style="HEIGHT: 28.55pt; mso-yfti-irow: 3"><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: windowtext 1.5pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 47.25pt; PADDING-RIGHT: 0cm; HEIGHT: 28.55pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="63">   ③</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 234.25pt; PADDING-RIGHT: 0cm; HEIGHT: 28.55pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="312">切断通向胰腺的所有神经，从另一些动物的胃中取出少量部分被消化了的食物，导入十二指肠中</td><td style="BORDER-BOTTOM: windowtext 1pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 69.1pt; PADDING-RIGHT: 0cm; HEIGHT: 28.55pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1.5pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="92">     大量增加</td></tr><tr style="HEIGHT: 28.05pt; mso-yfti-irow: 4; mso-yfti-lastrow: yes"><td style="BORDER-BOTTOM: windowtext 1.5pt solid; BORDER-LEFT: windowtext 1.5pt solid; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 47.25pt; PADDING-RIGHT: 0cm; HEIGHT: 28.05pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="63">     ④</td><td style="BORDER-BOTTOM: windowtext 1.5pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 234.25pt; PADDING-RIGHT: 0cm; HEIGHT: 28.05pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="312">切断通向胰腺的所有神经，把一些相同成分的食物不经过胃而直接引入十二指肠中</td><td style="BORDER-BOTTOM: windowtext 1.5pt solid; BORDER-LEFT: medium none; PADDING-BOTTOM: 0cm; PADDING-LEFT: 0cm; WIDTH: 69.1pt; PADDING-RIGHT: 0cm; HEIGHT: 28.05pt; BORDER-TOP: medium none; BORDER-RIGHT: windowtext 1.5pt solid; PADDING-TOP: 0cm; mso-border-left-alt: solid windowtext 1.0pt; mso-border-top-alt: solid windowtext 1.0pt" valign="top" width="92">     不增加</td></tr></tbody></table>根据以上实验，下列推断最合理的是