The fourth proportion to 5, 8, 15 is-

Answer: Option D

Let the fourth proportional to 5, 8, 15 be x.
Then,
$$\begin{array}{rl}& \Rightarrow 5:8:15:x\\ & \Rightarrow 5x=8\times 15\\ & \Rightarrow x=\frac{8\times 15}{5}=24.\end{array}$$