Regarding sexual differentiation of the fetus: (A) Gonadal development begins at 5th week of intrauterine life, (B) Y chromosome determines the differentiation of ovaries, (C) Female external genitalia development is completed by 10 weeks, (D) Male sexual differentiation occurs earlier than females
Answer is A. OptionB: SRY Gene located on Y chromosome encodes Testis Determining Factor which leads to the development of male genital organs Option C&D: Development of external genitalia is similar in males and females till the 6th week of IUL(Indifferent stage)....later develops in the direction of hormones. REFERENCE: TEXTBOOK OF CLINICAL EMBRYOLOGY... VISHRAM SINGH SECOND EDITION..PAGE NO:277