A neutral deuterium atom has 1 electron, 1 proton, and 1 neutron. The electron orbits in a circular orbit with a radius of 0.575nm. How many particles are present in a neutral deuterium atom?
a) 1 electron, 1 proton, 1 neutron
b) 1 electron, 2 protons, 1 neutron
c) 2 electrons, 1 proton, 1 neutron
d) 2 electrons, 2 protons, 1 neutron