Ans: A
By the intercepts form of equation of straight line, we have
$\begin{array}{rcl}
\dfrac{\log_4 x}{3}+\dfrac{\log_8 y}{5} & = & 1 \\
\dfrac{\log_2 x}{3\log_2 4} +\dfrac{\log_2 y}{5\log_2 8} & = & 1 \\
\dfrac{\log_2 x}{6}+\dfrac{\log_2y}{15} & = & 1 \\
5\log_2 x+2\log_2y & = & 30 \\
\log_2 x^5+\log_2y^2 & = & 30\\
\log_2 (x^5y^2) & = & 30 \\
x^5y^2 & = & 2^{30} \\
x^5y^2 & = & (2^3)^{10} \\
x^5y^2 & = & 8^{10}
\end{array}$
