$A$ typical angiosperm anther is:

Identify the figure.

What is the approximate diameter of a pollen grain?

An anther has $1200$ pollen grains. How many pollen mother cells must have been there to produce them?

The male reproductive organ of a flower consists of:

$A$ - Only some cells of the sporogenous tissue are capable of giving rise to microspore tetrad.
$R$ - The microspores are arranged in a cluster of four cells - the microspore tetrad.