Match Column-I with Column-II and select the correct option from the choices provided.

Column-I | Column-II

a. Site of fertilisation of egg with the sperm

b. Site of implantation of embryo

c. Site of entry of sperm into the female reproductive tract

d. Site through which the waste materials generated by the developing embryo are removed

(i) Vagina (ii) Uterus (iii) Oviduct (iv) Placenta (v) Cervix

As per the NCERT chapter (Section 7.3.3(b)): "The egg is carried from the ovary to the womb through a thin oviduct or fallopian tube... The uterus opens into the vagina through the cervix... The sperms enter through the vaginal passage during sexual intercourse. They travel upwards and reach the oviduct where they may encounter the egg... The embryo is implanted in the lining of the uterus... The embryo gets nutrition from the mother's blood with the help of a special tissue called placenta."

Matching each site:

• a. Site of fertilisation of egg with sperm $\rightarrow$ Oviduct (iii) — the text explicitly states sperms "travel upwards and reach the oviduct where they may encounter the egg," i.e., fertilisation occurs in the oviduct, not the uterus.
• b. Site of implantation of embryo $\rightarrow$ Uterus (ii) — "The embryo is implanted in the lining of the uterus."
• c. Site of entry of sperm into the female reproductive tract $\rightarrow$ Vagina (i) — "The sperms enter through the vaginal passage during sexual intercourse."
• d. Site through which embryonic waste is removed $\rightarrow$ Placenta (iv) — "The developing embryo will also generate waste substances which can be removed by transferring them into the mother's blood through the placenta."

This gives a-(iii), b-(ii), c-(i), d-(iv), which is option B.

Why the distractors are wrong:

• Option A wrongly assigns fertilisation to the uterus (ii) instead of the oviduct, and implantation to the vagina (i) instead of the uterus — both reversed.
• Option C wrongly assigns fertilisation to the placenta (iv) — the placenta is a nutritive/excretory structure formed after implantation, not the site of gamete fusion — and swaps oviduct and vagina for c and implantation site to the oviduct.
• Option D correctly places 'a' at oviduct (iii) and 'd' at placenta (iv), but incorrectly swaps b and c: it puts implantation in the vagina and sperm entry in the uterus, contradicting the text, which states sperm enters via the vagina and the embryo implants in the uterus.