Assertion (A): SF6 cannot be hydrolysed but SF4 can be.

Reason (R): Six F-atoms in SF6 prevent the attack of H2O on sulphur atom of SF6

1. Both the assertion and the reason are correct statements and the reason is the correct explanation of the Assertion.

2. Both the assertion and the reason are correct statements and the reason is not the correct explanation of the Assertion.

3. The assertion is correct but the reason is the wrong statement.

4. The assertion is incorrect but the reason is a correct statement.

HINT: Steric hindrance in the case of SF6 
 is not easily hydrolysis because here S atom is surrounded by 6F atom so it's complected for  to attack  but in
case of  here S atom is surrounded by 4F atom so it's to attack by