Final answer:
The application of contours in project management aids in resource leveling, helping to distribute resources evenly over the duration of the project and prevent overallocation.
Step-by-step explanation:
The advantage of applying contours to activities in project schedules is D) Contours assist in resource leveling. Unlike their use in art or architecture where contour lines are meant to delineate shapes and create an illusion of form and depth, in project management, contours refer to the varying levels of resource usage over time in scheduling activities. Resource leveling ensures that the demand for resources does not exceed the available supply by distributing resources evenly across tasks over the project timeline, which can help prevent resource overallocation and ensure that critical portions of the project have the necessary resources when needed.