Answer
B
Work Step by Step
At $x= 0$, the function equals zero, narrowing down our options to B, C, D, and F.
$\lim\limits_{x \to -\infty}f(x) = 0 $ and $\lim\limits_{x \to +\infty}f(x) = 0 $, meaning the answer can only be B or D. At $x=\pi/2\approx 1.6$, $f(x) \approx 4/(2.7+1)\approx 1$
The answer is thus B.
