Q.

Assertion: Oral contraceptive pills and Copper-T do not prevent sexually transmitted diseases.
Reason: Sexually transmitted disease are transmitted by contact with mucous membranes of infected organs.

1 Both assertion and reason are correct and reason is the correct explanation of assertion.  
2 Both assertion and reason are correct but reason is not the correct explanation of assertion.  
3 Assertion is true but Reason is false.  
4 Assertion is false but Reason is true.  

Ans.

(1)

Sexually transmitted diseases are transmitted by contact with mucous membrane of infected organs and oral contraceptives pills and Copper-T does not prevent the sexually transmitted diseases. Thus, both assertion and reason are correct and reason is the correct explanation of the assertion.