Given below are two statements, one is labelled asAssertion (A) :and the other as Reason (R).Assertion (A):Generally an alloy of lead and tin is used as a material of the fuse wire.Reason (R):Alloy of lead and tin has a higher melting point than copper and aluminium.

1. A

   Both (A) and (R) are true, but (R) is not the correct explanation of (A)

   Both true, R not explaining A. R is false: the fuse alloy melts lower than copper or aluminium.

2. B

   (A) is false, but (R) is true

   (A) false. Lead–tin is the usual fuse mix.

3. C

   (A) is true, but (R) is false.

   (A) true, (R) false. Fuse wire is a lead–tin alloy because it has a low melting point, not a higher one.

4. D

   Both (A) and (R) are true and (R) is the correct explanation of (A)

   Both true and R explains A. R reverses the melting-point fact.

Summary. Official key is (c). Lead–tin fuse is used for its low melting point. Reason states the opposite.