Answer
$b, a,c$
Work Step by Step
Resistance is given by $\frac{\rho l}{A}$. Since all the materials are the same, we can disregard $\rho$, the resistivity, as it is an intensive property. Since the lengths are also the same, we only need to consider the area - more area means less resistance. Thus, the order is $b, a,c$ as b's area is 10, a's area is 16, and c's area is 18.
