Which statement best describes the value of fungi in the environment?

Which statement best describes the value of fungi in the environment?
  a. Fungi fix nitrogen from the air for use by plants.
  b. Fungi trap sunlight energy in the form of carbohydrates.
  c. Fungi release elements from organic matter.
  d. Fungi enrich the soil by decreasing the rate of decay of organic matter.
  e. Fungi remove toxic metals from the soil.

Question 2

Refer to the accompanying figure. What fungal structure is comprised of a mass of threadlike strands of cells, attached
  one to the other?
  a. mycelium
  b. protistans
  c. mycorrhizae
  d. stolons
  e. rhizoids