Shrews Have Been Documented to Travel Across Frozen Lakes and Establish

Multiple Choice

Shrews have been documented to travel across frozen lakes and establish populations on previously uninhabited islands; thus,the shrews have a limited gene pool.If this limited gene pool has allele frequencies that are very different from the allele frequencies found in the original population,then this would be an example of:

A) natural selection.
B) population bottleneck.
C) divergent evolution.
D) founder effect.