Flower structure and development

Correct answer: B. Exine

Explanation: The governing concept is the structural organisation of a pollen grain. Its outer wall is called the exine, so option B is correct. Exine contains sporopollenin, an exceptionally resistant material that protects pollen from drying, physical injury, and chemical or biological attack. Intine is the inner wall. Nucellus is tissue inside an ovule, and tapetum is a nutritive layer in the anther.

Correct answer: B. Intine

Explanation: The governing concept is the two-layered wall of a pollen grain. Intine is the inner wall, making option B correct. It is generally thinner than the exine and is mainly composed of cellulose and pectic substances. During germination, the pollen tube emerges through the intine and grows toward the ovule. Exine is the resistant outer layer, while style and micropyle are parts of other reproductive structures.