The best answer in this case is C, "the researchers applied creativity to solve a problem in running an experiment".
Distributing the computing load across the global community by sharing processing power is a creative response to tackle the challenge in simulating protein folding for the experiment. This does not change or reduce the scientific merits of the experiment, so we can discount the first two answers (a & b). Answer d talks about well established scientific techniques, although the question wasn't really centered around the specific techniques, so it's not as relevant an answer as C.
The anwser should be B. Nonrenewable resources generally have a higher impact on the environmental than renewable resources.
Each bone has a humerus. The ones that have these bones are humans, lions and birds
Grow, reproduce, take in nutrients from the environment, respond to the environment, transport materials thru-out their body, produce chemicals
Food web stability is most dependent on the number of connections among species.
