题目

For each blank in the following passage there are four words orphrases marked A, B, C and D. Fill in each blank with the word or phrase thatbest fits the context. Almostall animals sleep, but do they dream? We certainly can't ask animals if theydream, but we can at least1theevidence that they might. There are two ways in which scientists have goneabout this seemingly 2 task. One is to look at their physicalbehavior during the various stages of the sleep cycle. The second is to seewhether their sleeping brains work similarly to our own sleeping brains. Thestory of how we 3 how to look into the 番茄果实的红色对黄色为显性，两室对多室为显性，植株高茎对矮茎为显性。三对相对性状分别受三对同源染色体上的等位基因控制。育种工作者用纯合红色两室矮茎番茄与纯合黄色多室高茎番茄杂交得到F1，F1由交，产生F2。下列有关叙述错误的是(    )A．F2代中的表现型共有8种B．F1可产生8种不同基因组合的配子C．F2代中的基因型共有27种D．三对性状的遗传不遵循基因的自由组合定律