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.
Vacuoles are essentially sacs surrounded by a membrane. They are used by cells as temporary storage sites. They often store food, enzymes, and other materials needed by the cell, and some vacuoles store waste products.
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Answer:
This voice box occurs in all amphibians but is anatomically most complex in frogs. The larynx exits into the trachea; the latter bifurcates into the bronchi and then into the lungs. The glottis then opens, and elastic recoil of the lungs forces the pulmonary air out and over the new air in the buccopharyngeal pocket.
Explanation:
Enzymes (Catalysts) lower the required activation energy, allowing the reaction to happen more quickly.