Which of the following substances is obtained from a tree?

1. A

   Asafoetida

   Asafoetida (hing) is an oleo-gum-resin obtained from the tap root and rhizome of Ferula plants (chiefly Ferula assa-foetida). Among the four, this is the tree/plant exudate, so (a) is the official key.

2. B

   Bitumen

   Bitumen is a petroleum-derived hydrocarbon binder used in roads, not a product tapped from a tree.

3. C

   Tincal

   Tincal is crude borax, a mineral borate from lake deposits, not a botanical exudate.

4. D

   None of the above

   None of the above would discard asafoetida, which is the plant product in the list.

Summary. Official key is (a) asafoetida. Hing is collected from Ferula roots; bitumen is fossil hydrocarbon and tincal is mineral borax. Do not confuse hing with mineral ‘shilajit’ in other lists. Honour the stored letter (a).