Please help!
Students in Ms. Brown's class are making observations in the garden outside of the school. They make a list of all the abiotic and biotic factors in their notebook. Part of the list is below:

Gravel
Grass
Butterfly
Sunflower
Bird feeder
Flowerpots

Which items on the list are a part of the garden ecosystem?

A- Gravel, bird feeder, flowerpots
B- All the listed items are part of the ecosystem
C- None of the listed items are a part of the ecosystem
D- Grass, butterfly, sunflower