At 20 $\degree$ C an Aluminum Ring Has an Inner Diameter of 5

Multiple Choice

At 20 $\degree$ C an aluminum ring has an inner diameter of 5.000 cm,and a brass rod has a diameter of 5.050 cm.Keeping the brass rod at 20 $\degree$ C,which of the following temperatures of the ring will allow the ring to just slip over the brass rod? (a_Al = 2.4 x 10^-5 /C $\degree$ ,a_brass = 1.9 x 10^-5/C $\degree$ )

A) 111 $\degree$ C
B) 236 $\degree$ C
C) 384 $\degree$ C
D) 437 $\degree$ C