The vegetative cell (tube cell) and generative cell are of unequal sizes. This is because 

• A

  In future, vegetative cell will undergo mitosis 

• B

  In future, generative cell will undergo meiosis

• C

  The microspore or pollen grain which produces these cells forms asymmetric spindle during mitosis.

• D

  Generative cell possess more cytoplasm than vegetative cell