[tex]\frac{x+2}{4x^{2}+5x+1 }*\frac{4x+1}{x^{2}-4 }=\\ \\\frac{x+2}{4x^{2}+4x+x+1 }*\frac{4+1}{(x-2)(x+2)}=\\\\\frac{(x+2)}{(x+1)(4x+1)}*\frac{(4x+1)}{(x-2)(x+2)}=\\ \frac{1}{(x+1)(x-2)} \\[/tex]
So the answer is A.
Hope this can help :)
