Match List-I (Altitudinal zones of eastern Himalayas) with List-II (Floras) and select the correct answer:

List-I	List-II
a. Tropical	1. Rich in conifers and bamboos (Arundinaria spp.)
b. Upper temperate	2. Composed of Shorea robusta with patches of riverain mixed deciduous forests, savannahs and swamps
c. Alpine	3. Composed of Rhododendron and Juniperus species

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

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

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

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

Answer: Option D