The area marked as `A` on the given map of India represents tropical evergreen forest. The other options can be dissected to understand why they are not the correct answer.

Option 1: Tropical rainforest - This type of vegetation is characterized by high annual rainfall, dense canopy layers, and high biodiversity. Although India does have some regions with dense forests, particularly in the northeastern states, the area marked as `A` on the map does not correspond to the typical characteristics of a tropical rainforest.

Option 3: Tropical deciduous - This vegetation type is commonly found in regions with distinct wet and dry seasons. Tropical deciduous forests lose their leaves during the dry season. However, the area marked as `A` does not align with regions known for tropical deciduous forests in India.

Option 4: Tropical scrub forest - This type of vegetation is typically found in regions with low rainfall and poor soil. It consists of short, shrubby plants. Again, the area marked as `A` does not match the characteristics of tropical scrub forests.

Therefore, the correct answer is option 2: Tropical evergreen forest. This type of forest is characterized by a dense canopy throughout the year, receiving high rainfall and having high biodiversity. The area marked as `A`