$\begin{array}{1 1}(A)\;\text{For a banyan tree ecosystem,the population density should be measured by its biomass}\\(R)\;\text{Number undermines the huge role of banyan tree in the ecosystem}\end{array}$

Question

$\begin{array}{1 1}(a)\;\text{Both statements are correct & (R) is the correct explanation of (A)} \\ (b)\;\text{Both statements are correct & (R) is not the correct explanation of (A)} \\(c)\;\text{(A) is correct,(R) is false} \\(d)\;\text{(A) & (R) both are incorrect}\end{array}$