Which white blood cell type are concentrated in the lining of respiratory passages, are important ...

Which white blood cell type are concentrated in the lining of respiratory passages, are important phagocytes that
  protect the lungs, and present antigens to T cells?
 
  a. B lymphocytes
  b. macrophages
  c. neutrophils
  d. dendritic cells
  e. mast cells

Question 2

Receptors for activated complement proteins are found on ____.
 
  a. dendritic cells, macrophages, and neutrophils
  b. mast cells, macrophages, and neutrophils
  c. dendritic cells, B lymphocytes, and neutrophils
  d. dendritic cells, eosinophils, and macrophages
  e. monocytes, T lymphocytes, and B lymphocytes