Answer
12
Work Step by Step
In a standardized test, time is a factor. You should look for shortcuts to find each answer as quickly as possible.
To find the coefficient of the $x^2$ term it is not necessary to multiply the entire polynomial. Identify the term that will give $x^2$ when multiplied by $4x$ and find that coefficient.
$4x\times3x=12x^2$ so the coefficient of the $x^2$ term is 12.