Three different gases, one monoatomic, one diatomic and one triatomic are expanded adiabatically under similar conditions, i.e., their final and initial conditions are the same. The least amount of work is done in the case of which gas?

Question

$\begin{array}{1 1}\text{(A) Insufficient data to answer the question} \\ \text{(B)diatomic} \\ \text{(C)triatomic } \\ \text{(D)monoatomic } \end{array}$