1. protons plus neutrons
2. proton number
3. neutral charge
4. positive charge
5. smallest particle to retain characteristics
6. negative charge
atomic mass
atom
electron
proton
neutron

1 protons plus neutrons  ~Atomic mass

2 proton number( Atomic number )

3 neutral charge~Neutron

4 positive charge~proton

5 smallest particle to retain characteristics  ~atom

6 negative charge~electron

the answer is c

tell me if wrong

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