Which of the following would increase mechanical advantage in a pulley system?

Increasing the mechanical advantage in a pulley system allows lifting heavier loads with less effort. One way to achieve this is by adding more pulleys to the system. Each additional pulley allows for the load to be distributed across more segments of rope, which in turn reduces the amount of force needed to lift the weight.

When more pulleys are added, the configuration changes to a block and tackle system, which increases the ratio of load to effort. For example, with a simple fixed pulley, you only change the direction of force, but as you add more pulleys, each one increases the mechanical advantage, allowing for easier lifting. The more pulleys you incorporate, the lighter the load feels, as the same amount of force can lift a heavier weight more efficiently.

Other factors, such as the length of the rope or the number of weights, do not have the same effect on mechanical advantage. In fact, using fewer pulleys or heavier weights would increase the effort required rather than improving mechanical advantage. Thus, adding more pulleys is the correct answer to enhance the efficiency of the pulley system.