Answer
C
Work Step by Step
Because the equations in 43-46 are all expressed in slope-intercept form ($y=mx+b$) and all have the same slope ($m$ value), the easiest way to match the graphs to their equations is by using the $y$ intercept ($b$ value).
The equation $f(x)= 3x + 1$ has a $b$ value of 1, so it matches to the line in graph C, which crosses the y axis at (0, 1).