Which of the following statements is false?

Which of the following statements is false?
  a. Sharks teeth are modified scales that are
  continuously shed and replaced.
  b. Many fish use a swim bladder to provide
  buoyancy control.
  c. The bony fishes were the ancestors of the
  cartilaginous fishes.
  d. The ray-finned fishes are the most numerous and
  diverse of the fish groups.
  e. The lobe-finned fishes are represented today
  only by the coelacanths.

Question 2

All EXCEPT which of the following have
  cartilaginous skeletons?
  a. sharks
  b. lampreys
  c. perch
  d. Manta rays
  e. stingrays