Answer:
I think B because white blood cells fight off bacteria and stuff. I hope this is right for you! if not I am sorry! Have a great holiday.
Answer:Generally, the longer ago the last common ancestor lived, the less the organisms have in common. Turtles and tortoises share a common ancestor, but began evolving separately a long time ago. ... Scientists can compare the DNA of two organisms; the more similar the DNA, the more closely related the organisms.