Pollen tablets are available in the market for

Which one of the following is resistant to enzyme action?

Assertion : If pollen mother cells has $42$ chromosomes, the pollen has only $21$ chromosomes.
Reason : Pollens are formed after meiosis in pollen mother cell.

Find out the odd one.

$A$ : Restitutional nucleus can be observed in endothecium cells.
$R$ : Endothecium cells are usually triploid.