Final answer:
In the equation y = mx + b, 'm' represents the slope of the line, and 'b' is the y-intercept where the line crosses the y-axis.
Step-by-step explanation:
In the slope-intercept form of a line, which is y = mx + b, m represents the slope of the line, and b represents the y-intercept of the line. The slope, m, indicates the steepness of the line and is calculated as the rise over the run between two points on the line. The y-intercept, b, is the point where the line crosses the y-axis, which occurs when the value of x is zero.
Therefore, the correct answer to the question would be 'd. m is the slope, and b is the y-intercept.'