Which of following statements about catalysts is not true?

Question

$\begin{array}{1 1} \text{(a)They speed up a chemical reaction}\\\text{(b) They reduce the time taken to reach equilibrium}\\ \text{(c) They have effect on the position of equilibrium once it is reached} \\ \text {(d) They have no effect on the position of equilibrium one it is reached} \end{array}$