how do I pick the right series

Question 5 Find the Maclaurin series for f(x) using the definition of the Maclaurin series. f(x) = xcos(5x) OF (-1 )5 x 2+1 n=0 (2n)! O (1 )52n 2n +1 n=0 n! O (- 1 )52n x2n n=0 (2n)! O (-1) n52n x 2n+1 n=0 ( 2n)! O (- 1 ) +152n 2n +1 n=0 ( 2n)