The phenomenon wherein, the ovary develops into a fruit without fertilisation is called:
A. Parthenocarpy

B. Apomixis

C. Asexual reproduction

D. Sexual reproduction

Parthenocarpy is development of a fruit without prior fertilization. Hence the fruits are seedless. So in this the ovary develops into a fruit without fertilisation.

Apomixis is development of a seeds without prior fertilization. It is observed in few flowering. Apomixis is a form of asexual reproduction that mimics sexual reproduction. Apomixis avoids the processes of meiosis and fertilization, leading to embryo development.

Vegetative propagation is type of asexual reproduction in a plant where new plant is formed with involvement of just one parent. The new plant is genetically identical to the parent.

Sexual reproduction – here new offspring is formed with involvement of two parents.

Therefore, the correct answer is option (a).