Consider the series ∑n=1∞(−1)nnn2+1\sum_{n=1}^{\infty} (-1)^n \frac{n}{n^2+1}∑n=1∞(−1)nn2+1n. Which of the following is true?
It converges absolutely.
It converges conditionally.
It diverges.
It converges by the Ratio Test.