sat-dog

Choice A is correct. Since $2$ is a common factor of each of the terms in the given expression, the expression can be rewritten as $2\left(x^2+19x+5\right)$. Therefore, the factors of the given expression are $2$ and $x^2+19x+5$. Of these two factors, only $2$ is listed as a choice.

Choice B is incorrect and may result from conceptual or calculation errors.

Choice C is incorrect. This is a term of the given expression, not a factor of the given expression.

Choice D is incorrect. This is a term of the given expression, not a factor of the given expression.