Match List I with List II related to embryonic development at various months of pregnancy : List I List II A. The foetus movement starts and hair appears on the head I. 24 weeks of pregnancy B. The foetus develops limbs and digits II. 20 weeks of pregnancy C. The foetus develops external genital organs III. 8 weeks of pregnancy D. The foetus body is covered with fine hair; eyelids separate and eyelashes are formed IV

Step-by-step solution

According to the standard textbook on human reproduction: By the end of the second month ( 8 weeks) of pregnancy, the foetus develops limbs and digits. Thus, B matches III. By the end of 12 weeks (first trimester), most of the major organ systems are formed, including well-developed external genital organs. Thus, C matches IV. During the fifth month ( 20 weeks), the first movements of the foetus and the appearance of hair on the head are observed. Thus, A matches II. By the end of about 24 weeks (end of the second