We have a right triangle with two of the legs known (7 and 4). The hypotenuse is unknown. Because of this, we will use the tangent trigonometric function.
Tangent of an angle is equal to the ratio of the opposite and adjacent sides tan(angle) = opposite/adjacent
Divide those two sides to get opposite/adjacent = 7/4 = 1.75
Look through the table and see which value in the "tan(x)" column is closest to 1.75, and that happens to be 1.7321. It is in the bottom row corresponding to 60 degrees.
So the final answer is choice D) 60 degrees
Note: it turns out that the angle theta is roughly 60.2551187 degrees