Particle A has very little mass in comparison to Particle B. Both particles are in the same atom. Which is the best conclusion about Particles A and B?

Question

They have the same charge.
They are located in the nucleus together.
Particle A has a positive charge, and Particle B is neutral.
Particle A orbits the nucleus, and Particle B is located in the nucleus.

Answer 1

The best conclusion about Particles A and B, given that Particle A has very little mass in comparison to Particle B and both particles are in the same atom, is:

Particle A orbits the nucleus, and Particle B is located in the nucleus.

In an atom, protons and neutrons (which make up the nucleus) have much greater mass than electrons. Typically, electrons (Particle A) orbit the nucleus (where protons and neutrons, Particle B, are located).