More Than 800 Species of Drosophila Occur in the Hawaiian

More than 800 species of Drosophila occur in the Hawaiian Islands, representing 30 to 40 percent of all the species in this genus. The occurrence of so many Drosophila species in this island chain is

A) the result of many founder events followed by genetic divergence.
B) an example of an evolutionary radiation.
C) largely the result of sympatric speciation.
D) evidence that the genus Drosophila first evolved in the Hawaiian Islands.
E) Both a and b