Find Two Real Numbers B Such That the Expression $x ^ { 2 } + b x + 196$

Multiple Choice

Find two real numbers b such that the expression $x ^ { 2 } + b x + 196$ is a perfect square trinomial.

A) $\pm 14$
B) $\pm 15$
C) $\pm 42$
D) $\pm 196$
E) $\pm 28$