Electron is the elementary particle that has an antiparticle with the same mass but opposite electrical charge. An antiparticle is a particle that has the same mass as its corresponding particle but carries the opposite charge.

Below is a detailed explanation for each option:

a) Proton: The proton is a positively charged elementary particle found in the nucleus of an atom. Its antiparticle is called the antiproton, which has the same mass as a proton but carries a negative charge. Therefore, the antiparticle of a proton does not have the same electrical charge as the proton.

b) Neutron: The neutron is a neutral elementary particle found in the nucleus of an atom. Since it has no electrical charge, its antiparticle would also have no charge. Therefore, the antiparticle of a neutron does not have the same electrical charge as the neutron.

c) Electron: The electron is a negatively charged elementary particle found orbiting the nucleus of an atom. Its antiparticle is called the positron, which has the same mass as an electron but carries a positive charge. The positron is the antiparticle of the electron and has the same mass but opposite electrical charge. Therefore, the correct answer is option 'C'.

d) Neutrino: The neutrino is a neutral elementary particle with very little mass. It is not electrically charged, so it does not have an electrical charge to be opposite to. Therefore, the antiparticle of a neutrino does not have the same electrical charge as the neutrino.

In summary, the electron is the elementary particle that has an antiparticle with the same mass but opposite electrical charge. The antiparticle of an electron is called a positron, which has the same mass as an electron but carries a positive charge.