Correct answer is (c) 18.24
To explain I would say: Applying nodal analysis at node ‘a’, (Va-20∠30^o)/3+Va/(-j4)+Va/(2+j5)=0. On solving, Va = 16.27∠18.91⁰. Current in 2Ω resistor I2 = Va/(2+j5) = (16.27∠18.91^o)/(5.38∠68.19^o)=3.02∠-49.28^o. Power dissipated in 2Ω resistor P=I2^2 R=3.02^2×2 = 18.24W.