Identify the type of flower $A$ and $B$ in the given diagram.

Choose the correct option for the given statements:
$(i)$ In western countries, a large number of pollen products in the form of syrups are available in the market.
$(ii)$ In rice, pollen grains lose viability within $30$ minutes of their release.
$(iii)$ Pollen grains are stored at $-196^{\circ}C$ (cryopreservation) in liquid nitrogen, not at room temperature, for future use.
$(iv)$ Pollen grains are released from the anther, not from the seeds of wheat and rice.

An angiospermic male plant with $24$ chromosomes in its pollen mother cells is crossed with a female plant bearing $24$ chromosomes in its root cells. What would be the ploidy of the embryo and endosperm respectively formed after this cross?

The chromosomal number in a cell of a flowering plant is:

What is gamete transfer? State its necessity.

Which of the following plant families has $polysiphonous$ pollen grains?