Q: Fact 1: Burning wood is used to produce heat. Fact 2: All wood is either pine or oak. Given the two facts above, what is burned to produce heat?

Possible answers:
[I] pine.
[II] wood.
[III] gravity.
[IV] Coal.
[V] clouds.
[VI] oak.
[VII] elms.
[VIII] air.
The answer is:
[VI]