Answer (C) is correct. Simple regression uses the algebraic formula for a straight line, y = a + bx, where x is the independent variable. Multiple regression is used when there is more than one independent variable. Multiple regression allows
a firm to identify many factors (independent variables) and to weight
each one according to its influences on the overall outcome (y = a +
b1x1 + b2x2 + b3x3 + etc.).