There is insufficient information to determine the length of BC because we do not know the position of point B along line AC. Without knowing the specific lengths of AB or BC, we cannot calculate BC's length.
The question does not provide enough information to determine the length of BC. Collinear points mean that points A, B, and C lie on the same straight line. However, without additional information regarding the position of B relative to A and C, or the length of AB or BC specifically, we cannot calculate the length of BC. Point B can be anywhere on the line segment AC, making BC any length from 0 up to 16. The provided options (a) 16, (b) 8, (c) 32, (d) 24, cannot be determined to be accurate without further details. This exemplifies an understanding of collinear points and the indeterminacy when lacking adequate information on segment lengths.