Apomictic seeds are formed due to

The correct option is D All of the above.

There are several ways in which apomictic seeds are formed. In some species, diploid egg cell formed without reduction division or meiosis will develop into an embryo without fertilisation. In such cases there is no recombination of genes. Sometimes sporophytic cells like nucellar cells and integumentary cells protrude into the embryo sac and develop into embryos.