For gas exchange to occur quickly and efficiently, which type of epithelium must be present on all ...

For gas exchange to occur quickly and efficiently, which type of epithelium must be present on all respiratory surfaces?
  a. pseudostratified columnar epithelium
  b. simple squamous epithelium
  c. ciliated columnar epithelium
  d. stratified squamous epithelium
  e. ciliated squamous epithelium

Question 2

Lungs absorb oxygen from inhaled air, and the small intestine move ingested material through the digestive tract and
  absorbs nutrients from ingested food. Which statement describes the type of epithelium you would expect to line each of
  these surfaces?
  a. They are both lined by a simple squamous epithelium.
  b. They are both lined by a simple cuboidal epithelium.
  c. The lungs are lined by a simple squamous epithelium, and the small intestine is lined by a ciliated columnar
  epithelium.
  d. The lungs are lined by a columnar epithelium, and the small intestine is lined by a simple squamous
  epithelium.
  e. The lungs are lined by a simple squamous epithelium, and the small intestine is lined by a simple cuboidal
  epithelium