In the 1960s, a drug called thalidomide, ironically prescribed for morning ... ...

In the 1960s, a drug called thalidomide, ironically prescribed for morning sickness, was responsible for the malformation of several babies. In general, at what time during pregnancy would it be most dangerous to take a drug that is toxic or harmful to the developing child?
(A) During the zygote stage
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in 18. Reproductive Systems, Gametogenesis, and Early Development