Question

The partial graph of a 4th-degree polynomial function P(x) is shown. The leading coefficient is 1 and the x-intercepts of the graph are integers.

If the polynomial function is written in the form P(x) = c(x - a)^2 (x - b)(x + d), where a, b, c, and d are all positive integers, then what is the value of a?

Choices:
1
3
4
12