The chief source of resin (Raal) in Uttarakhand is

Toon
Oak
Pine
Deodar

The correct answer is (d) Deodar.

Deodar is a coniferous tree that is native to the Himalayas. It is the state tree of Uttarakhand. Deodar trees are known for their high-quality resin, which is used in a variety of products, including varnish, turpentine, and incense.

Toon is a deciduous tree that is native to the Indian subcontinent. It is not a major source of resin.

Oak is a deciduous tree that is native to the Northern Hemisphere. It is not a major source of resin.

Pine is a coniferous tree that is native to the Northern Hemisphere. It is a major source of resin, but it is not the chief source of resin in Uttarakhand.