Identify A, B, C and D in the schematic representation of oogenesis.

The correct option is C A-Mitosis and differentiation, B-Meiosis I, C-First polar body, D-second polar body
Oogenesis (process of formation of mature female gamete) is initiated at embryonic stage to form oogonia. Oogonia undergoes mitosis and differentiation. These cells undergo prophase-I of meiosis-I and get arrested at this stage to form primary oocytes. The primary oocyte within the tertiary follicle grows in size and completes its first meiotic division. It is an unequal division resulting in the formation of a large haploid secondary oocyte and a tiny first polar body. Secondary oocyte completes meiosis to give ovum and secondary polar body.