Help with b please!!

there form

Explanation:

one shows a string appearance when the other is like a germ cell

Depending on if your speaking of a human or animal.  The kind of animal matters as well.  Hind limbs tend to be stronger like with frogs and rabbits because they use them to jump and kick.  With animals like squirrels, there forelimbs are used for picking up food.  Hind limbs are also longer on many animals.