Match List-I (Kinds of aperture) with List-II (Characteristic features) and select the correct answer:

List-I	List-II
a. Sulcus	1. A round aperture if present in small numbers pori are found in the equatorial region
b. Colpa	2. A longitudinal furrow is found to the distal half of the pollen grain, crossing the pollar axis at right angles
c. Ruga	3. A meridional furrow crossing the equator at right angles and directed at each end to the polls of the pollen grain
d. Porus	4. A furrow is found irregularly on the grain surface

A. a-2, b-4, c-3, d-1

B. a-3, b-4, c-2, d-1

C. a-2, b-1, c-4, d-3

D. a-2, b-3, c-4, d-1

Answer: Option D