Many Plants Have Evolved Mutualistic Relationships with Nitrogen-Fixing Bacteria Because

Multiple Choice

Many plants have evolved mutualistic relationships with nitrogen-fixing bacteria because:

A) The bacteria transform nitrogen into useful forms for the plants; the plants provide carbohydrates
B) The bacteria protect the plant from harmful effects of nitrogen compounds such as ammonia; the plants provide carbohydrates for the bacteria
C) The bacteria utilize nitrogen to produce energy for the plants; the plants provide the source of the nitrogen for the bacteria
D) The bacteria provide natural immunities to the plants; the plants shelter the bacteria from predators
E) There is not a mutualistic relationship between nitrogen-fixing bacteria and plants