Danielle lives with her family on a farm. In school, she has been learning about the nitrogen cycle kin science class. She knows that her father pread a nitrogen-based fertilizer on a patch of grass recently where the cows graze in the field. Why was it necessary to add a nitrogen-based ertilizer to the soil where there was a patch of grass? A because plants cannot use "free" nitrogen
B because nitrogen can only be "fixed” by lightning
C because bacteria released all of the nitrogen into the air
D because there are no decomposers on the farm