Fertilization takes place in:

The correct answer is Option (2) → Fallopian tube

Fertilisation is the fusion of a sperm with an ovum. In humans it takes place in the ampullary region of the fallopian tube (oviduct). The ovum released from the ovary is carried to the ampulla, and the sperms swim up to the same place. Fertilisation can happen only if both reach the ampulla at the same time.

(1) Uterus — Incorrect. The uterus is where the blastocyst gets embedded later. This is implantation, not fertilisation.

(2) Fallopian tube — Correct. Fertilisation happens in its ampullary region.

(3) Ovary — Incorrect. The ovary makes and releases the ovum (ovulation). The ovum is not fertilised there.

(4) Vagina — Incorrect. Semen is released into the vagina during coitus (insemination). The sperms then have to travel up to the fallopian tube.

NCERT Extract:
Fertilisation and Implantation – “… During copulation (coitus) semen is released by the penis into the vagina (insemination). The motile sperms swim rapidly, pass through the cervix, enter into the uterus and finally reach the ampullary region of the fallopian tube (Figure 2.11b). The ovum released by the ovary is also transported to the ampullary region where fertilisation takes place. Fertilisation can only occur if the ovum and sperms are transported simultaneously to the ampullary region.”