After a drought in 1977, researchers hypothesized that on the Galapagos Island Daphne Major, medium ground finches with large, deep beaks survived better than those with smaller beaks because they could more easily crack and eat the tough Tribulus cistoides fruits. A tourist company sets up reliable feeding stations with a variety of bird seeds (different types and sizes) so that tourists can get a better look at the finches. Which of the following events is now most likely to occur to finch beaks on this island?

A. Phenotypes are not determined by genes.

B. The environment can also affect phenotype.

C. Evolution of yet larger, deeper beaks over time, until all birds have relatively large deep beaks

D. All traits are encoded by a single gene.

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