Depends on the element it can by up to 3, 8, or maybe 16.
I believe it is C but if not that A
Compound is a molecule made of atoms from different elements. Allcompounds are molecules, but not allmolecules are compounds. Hydrogen gas (H2) is a molecule, but not a compound because it is made of only one element.
The first one is Producer and second level consumer
the second one is: decomposer and producer
the third one is: carnivore and second level consumer
the fourth one is: herbivore and first level consumer