Question

A particle having almost zero mass and exactly zero charge is

• A. positron
• B. electron
• C. neutron
• D. neutrino

Answer 1

Answer: (D)

neutrino

Answer 2

We know that the neutrino is the particle which has almost zero mass and exactly zero charge. Positron has the charge $+e$ and mass $m_{e}$ [equal to electron mass].
Electron is a particle which has - $e$ charge and $9.1 \times 10^{-31} kg$ mass.
Neutron is a particle which has zero charge and $1838 m_{e}$ mass.
So, the required answer is neutrino.