Most of the energy that passes through a food chain is lost to the environment as
heat
matter
chemical
mechanical

idk but if i had to take an educated guess i’d say a c d

The proton has a positive charge while the neutron has no charge they both make up the nucleus of the atom while the elections have a negative charge and surround the nucleus of the atom. the protons and electrons are used to calculate the atom's mass whereas the neutrons don't affect the mass