If \(\mu=\{\) integers \(\leq 20\}, \mathrm{X}=\{\) multiples of 4\(\}, \mathrm{Y}\) \(=\{\) multiples of 3\(\}\), the elements of \(X^{\prime} \cap \mathrm{Y}\) are ____________
A. \(\{12\}\) B. \(\{3,6,9,12,15,18\}\) C. \(\{3,6,9,15,18\}\) D. \(\{4,8,16,20\}\)
