Long-term studies of Belding's ground squirrels show that individuals are known to emigrate up to 2 kilometers from where they are born. Over time, immigrants comprise up to 8% of individuals in the new population. Which of the following answers describes an evolutionary benefit from immigration among populations?

A) These immigrants coming into the new populations make up for the deaths of individuals, keeping the populations' size stable.
B) These immigrants provide a source of genetic diversity for the receiving populations.
C) Those individuals that emigrate to these new populations are looking for less crowded conditions with more resources.
D) Gradually, the populations of ground squirrels will move from a clumped to a uniform population pattern of dispersion.