Question 5
Which subatomic particle carries no charge?
The right answer is the one marked above.
The neutron. The proton has a positive charge and the electron a negative one; the neutron has none at all.
Keep charge and mass apart, because they behave quite differently here. The neutron carries no charge but has almost the same mass as a proton. The electron carries a full charge but has about 1/1840 of a proton's mass.