As per Koppen's classification of climate, which one of the following is the suitable description of North-East India including North Bengal? [UK-PSC 2016]

• A.  Tropical monsoon rainforest (Amw)
• B.  Sub-tropical monsoon rainforest (Am)
• C.  Tropical wet and dry climate (Monsoon Savannah) (Aw)
• D.  Humid sub-tropical climate with dry winter (Cwg)