Which of the following series does the alternating test ensure convergence?

1. For which of the following series does the alternating test ensure convergence! O C(-1) n=0 O M 8 (n?)! 1=0 (2n) ! O C(-1)" n-0 O C(-1)"In+1 n O E(-1)" arctan n=1 0 C(-1)2 (3n - 1\\ n n=1 n2 0 M (n!)? (2n)! 2n - 1 M: 2n + 1 0 E(-1)" In2 cos n=1 _(-1)" arctan(#n) n=1