# If the sum of the coefficients in the expansion of $(b+c)^{20}[1+(a-2)x]^{20}$ is square of the sum of the coefficients in the expansion $[2bcx-(b+c)y]^{10}$ where $a,b,c$ are positive constants, then $a,b,c$ satisfies the equation?
$\begin{array}{1 1} (A) bc+ac=2bc \\ (B) ab+ac+bc=0 \\ (C) ac+bc=2ab \\ (D) ab+ac=2bc \end{array}$