What is the composition of mud rocks ?

Question

$\begin{array}{1 1} (a)\; \text{20 - 25 % of sandstones } \\ (b)\;\text{65 % of mudstone, shale and siltstone } \\ (c)\; \text{6 % of limestone and 60 % sandstones} \\ (d)\; \text{16 % granites and 12 % mudstones} \end{array}$