Two identical rods are connected between two containers one of them is at 100∘C and another is at 0∘C . If rods are connected in parallel then the rate of melting of ice is q1 gm/sec. If they are connected in series then the rate is q2 . The ratio q2/q1 is
a. 2
b. 4
c. 1/2
d. 1/4