A piece of wire of resistance R is cut into five equal parts. These parts are then connected in parallel. If the equivalent resistance of this combination is R?, then the ratio R/R? is: (a) 1/25 (b) 1/5 (c) 5 (d) 25

Resistance is proportional to the length of wire and inversely proportional to the area of cross-section. IF length is 1/5th, then Resistance is also 1/5 th of the original value.