Propped Cantilever Beam AB Has Moment $M_{\mathrm{1}}$ Applied at Joint B $M_{2}$

Propped cantilever beam AB has moment $M_{\mathrm{1}}$ applied at joint B. Framework ABC has moment $M_{2}$ applied at C. Both structures have con-
Stant flexural rigidity EI. If the ratio of the applied moments $M_{1} / M_{2}=3 / 2$ the ratio of the joint rotations at B, $\theta_{B 1} / \theta_{B 2}$ , is approximately: (A) 1
(B) $3 / 2$
(C) 2
(D) $5 / 2$