If A = 1 + 2P and B = 1 + 2-P, then what is the value of B?

Answer: Option C

$$\begin{array}{rl}& A=1+2^P\\ & B=1+2^{-P}\\ & \text{Put }P=1\\ & A=3,B=\frac{3}{2}\\ & \text{Option C is correct}\\ & \\ & \mathbf{Alternate}:\\ & A=1+2^P......\left(\text{i}\right)\\ & B=1+2^{-P}\\ & =1+\frac{1}{2^P}\\ & =\frac{2^P+1}{2^P}\\ & =\frac{A}{A-1}\left(\text{from equation }\left(\text{i}\right)\right)\end{array}$$