Nucellar embryo is

In many plants,sexual reproduction is replaced by asexual reproduction,which is called......

In which of the following is apomixis observed?

Parthenogenesis occurs during which of the following processes?

Statement-$X$: Apomixis is seen in a few flowering plants such as some species of $Asteraceae$ and grasses.
Statement-$Y$: Apomixis is a form of asexual reproduction that mimics sexual reproduction.
Statement-$Z$: In some species of apomictic seeds,the diploid egg cell is formed without reduction division.

Polyembryony seen in $Cycas$ is: