Match the expressions below with the letters labeling their equivalent expressions.
You must get all of the answers correct to receive credit.

1. $\displaystyle \frac{1 }{x-2 } - \frac{1 }{x^2-4 }$
2. $\displaystyle \frac{1 }{x+2 } + \frac{1 }{x^2-4 }$
3. $\displaystyle \frac{1 }{x+2 } + \frac{1 }{x^2+4 }$

A. $\displaystyle \frac{x^2 +x +6 }{(x+2)(x^2+4) }$
B. $\displaystyle \frac{x-1 }{x^2-4 }$
C. $\displaystyle \frac{x+1 }{x^2-4 }$