1 . 12-12+12-12+.....

• A. $\frac{{\left(-1\right)}^n}{n+1}$
• B. $\frac{{\left(-1\right)}^{n-1}}{n+1}$
• C. $\frac{{\left(-1\right)}^{n+1}}{n+1}$
• D. $\frac{{\left(-1\right)}^{-n+1}}{n+1}$

Answer: Option C

Explanation: