Dog breeders maintain the purity of breeds by keeping dogs of ...

[j_sun]

Dog breeders maintain the purity of breeds by keeping dogs of different breeds apart when they are fertile. This kind of isolation is most similar to which of the following reproductive isolating mechanisms?
A) reduced hybrid fertility
B) hybrid breakdown
C) mechanical isolation
D) habitat isolation
E) gametic isolation

[coco]

Hey again

I'm guessing it's D. It makes sense.

[j_sun]

You're the best, thank you