Here's a problem to solve: A geological change separates a wolf population into two new populations. Genetic drift directly causes which effect in the two new populations over time?

Among the 4 following options, which is the correct answer?

- A: Their mutation rates increase.
 
- B: The presence and distribution of alleles diverge.
 
- C: They respond differently to the same selection pressures.
 
- D: They interbreed to maintain uniformity of traits.
 