The dimensional formula of resistance \( R \) is \( [ML^2T^{-3}A^{-2}] \) and the dimensional formula of capacitance \( C \) is \( [M^{-1}L^{-2}T^4A^2] \).
To find the dimension of \( CR \), we multiply the dimensions of \( R \) and \( C \):
\[
\text{Dim}(CR) = [ML^2T^{-3}A^{-2}] \times [M^{-1}L^{-2}T^4A^2] = [M^0L^0T^0]
\]
Thus, the dimension of \( CR \) is \( [M^0L^0T^0] \), which is a dimensionless quantity. Therefore, the correct answer is (B).