Identify the part labeled as '$A$' in the given figure.

Professor Birbal Sahni discovered a fossil plant from the $100$ million-year-old fossil forest located in Rajmahal Hills,Bihar. Which plant was it?

The giant tree among the pines belongs to

Statement $S$: $Sequoia$ $sempervirens$ is an example of an angiosperm.
Statement $R$: $Eucalyptus$ is the tallest tree in the world.

In gymnosperms,the microsporangium represents .......... .

If the haploid number of chromosomes in $Pinus$ is $12$,the number in its endosperm cells will be