[单选题]
Two masses M and m are connected by a rod orj2z,xk b 7i:dr 4go(nf negligible mass. They rotate aroy9s:7ea bbg3(:(ygcnqw 4 rsc und a vertical a :csa w g(qr7cy3y9:neg4(bbsxis as shown in the diagram.
The ratio
$frac{Distance between M and the axis}{Distance between m and the axis}$=$frac{1}{2}$
What is the moment of inertia?
A. $frac{L^2(M+m)}{4}$
B. $frac{L^2(M+m)}{9}$
C. ${L^2(M+m)}$
D. ${L^2(M+4m)}$
