When a new chain is installed on a competitive cyclist’s bicycle, the

When a new chain is installed on a competitive cyclist’s bicycle, the cyclist typically experiences immediate improvement in racing performance, and then within three weeks, on average, performance reverts to the level just prior to installation of the new chain. Based on this observation, a sports-performance researcher hypothesized that installing a new component, such as a chain, gives a competitive cyclist a psychological boost, which helps motivate that cyclist during a race.

Which of the following investigations is most likely to yield information that would be useful in evaluating the researcher’s hypothesis?

(A) Determine if amateur and professional cyclists experience a similar performance boost when new chains are installed on their bicycles.

(B) Determine if the materials used to make bicycle chains vary from one manufacturer to another.

(C) Determine how often a bicycle chain must be cleaned and oiled to maintain it in new condition.

(D) Determine if a competitive cyclist can tell merely by riding a bicycle whether it has a new chain or an older chain.

(E) Determine if a new chain exerts less gear friction, which in turn requires the cyclist to exert less effort, than a used chain.