Total number of meiotic divisions required for forming 100 zygotes or 100 grains of wheat is

The correct option is A 125
For the formation of 100 zygotes, 100 each of male and female gametes are required.

During microsporogenesis (formation of microspores which eventually develop into pollen grains), 1 cycle of meiosis produces 4 microspores. So, for the formation of 100 microspores, 100/4 = 25 cycles of meiosis are required.

During megasporogenesis (formation of megaspores, out of which, one functional megaspore eventually develops into embryo sac), 1 cycle of meiosis produces 1 functional megaspore. So, for the formation of 100 functional megaspores, 100 cycles of meiosis are required.

Hence, for the formation of 100 zygotes, the total number of meiotic divisions required is 100 + 25 = 125.