The milk of many mammals contains cannabinoids, substances that are known to stimulate certain receptors in the brain. To investigate the function of cannabinoids, researchers injected newborn mice with a chemical that is known to block cannabinoids from reaching their receptors in the brain. The injected mice showed far less interest in feeding than normal newborn mice do. Therefore, cannabinoids probably function to stimulate the appetite.
Which of the following is an assumption on which the argument depends?
Newborn mice do not normally ingest any substance other than their mothers' milk.
Cannabinoids are the only substances in mammals' milk that stimulate the appetite.
The mothers of newborn mice do not normally make any effort to encourage their babies to feed.
The milk of mammals would be less nutritious if it did not contain cannabinoids.
The chemical that blocks cannabinoids from stimulating their brain receptors does not independently inhibit the appetite.
E选项的意思是那个chemical本身并不会抑制食欲,而是因为它起到了阻断c物质的作用所以减少食欲,所以本质上是c物质的原因,而非chemical
新生老鼠通常不摄入任何物质,除了它们母亲的乳汁。
大麻素是哺乳动物的乳汁中唯一能刺激食欲的物质。
新生老鼠的母亲通常不会努力去鼓励它们的孩子进食。
如果哺乳动物的乳汁中不含有大麻素,那么它的营养价值就会降低。
阻止大麻素刺激大脑受体的化学物质并不能独立抑制食欲。
原文说cannabinoids的作用是 to stimulate the appetite.,而E取非抑制cannabinoids的化学物质本来就可以单独抑制食欲,也就是说是这个用来起抑制的化学物质导致的食欲下降,和cann....没关系
E 不是只有隔绝C的物质起着刺激大脑接收器的作用,这里要注意do not independently,如果只有隔绝C的物质起作用,就不能说明C在起作用,文章要说明的是C在起作用
排除他因,作为defender