Given below are two statements: 

Assertion (A):  Greenhouse effect was observed in houses used to grow plants and these are made of green glass.
Reason (R):  Greenhouse name has been given because glasshouses are made of green glass.

1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false but (R) is true.