Which of the following is least likely to be considered a mutualistic relationship?

Which of the following is least likely to be considered a mutualistic relationship?
 
  a. Bacteria living in the roots of pea plants.
 b. Bird nesting in a tree.
 c. Cyanobacteria living inside of an eukaryotic cell.
 d. Clownfish living in the tentacles of an anemone.
 e. Fungi living in the roots of plants.

Question 2

Which is the LEAST LIKELY result of a genetic bottleneck?
 
  a. complete elimination of the less common allele
  b. increase in the frequency of the less common allele
  c. allele frequencies identical to the previous generation
  d. decrease in the frequency of an uncommon allele
  e. decrease in the frequency of the most common allele