What is the result of 9x - 3x + 4?

To simplify the expression 9x - 3x + 4, you start by combining the like terms. The terms 9x and -3x are both coefficients of x. When you subtract 3x from 9x, you perform the operation:

9x - 3x = 6x.

This leaves you with the constant term, which is +4, that does not change. Therefore, after combining these terms, you get:

6x + 4.

This matches the answer option that presents 6x plus 4 as the result. Thus, this choice is indeed correct because it accurately reflects the simplification process of the given expression.