Effect of addition of insulation on heat transfer to metallic surface.

Question

Assertion (A): Addition of insulation to the inside surface of a pipe always reduces heat transfer rate and critical radius concept has no significance.    (IES-95)

Reason (R): If insulation is added to the inside surface, both surface resistance and internal resistance increase.

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

(b) Both A and R are individually true but R is not the correct explanation of A.

(c) A is true but R is false

(d) A is false but R is true