Study the following statements:
l) Pollen grains of many species cause severe allergies and bronchial afflictions in some people often leading to chronic respiratory disorders.
II) Pollen grains are rich in nutrients.
III) Carrot grass that came into India as a contaminant with imported rice. Choose the option for the correct statements:

Among the following statements related to pollens, choose the correct one.

Statement $\mathrm{I}$: In $40\%$ of angiosperms pollen grains are shed at the $3$—celled stage.

Statement $\mathrm{II}$: Intine is made of cellulose and pectin, and it is discontinuous with germ pores.

Assertion $\left(\mathrm{A}\right):$ Pollengrains are well preserved as fossils

Reason $\left(\mathrm{R}\right):$ The exine of pollen grains is made up of sporopollenin, which can withstand high temperatures, strong acids and alkali.

Assertion $\left(\mathrm{A}\right):$ Xenogamy involves transfer of pollen grains from the flower of one plant to the stigma of another plant.

Reason $\left(\mathrm{R}\right):$ This is the only type of pollination which brings genetically different types of pollen grains to the stigma.

The correct answer is:

Mateh the following?