Concept:The electron is a fundamental negatively charged subatomic particle.Explanation:J.J. Thomson discovered the electron in 1897 through experiments with cathode rays.He showed that cathode rays consist of tiny negatively charged particles, which he called electrons.This discovery proved that atoms are not indivisible, as previously thought.Among the given options, J.J. Thompson is the correct scientist associated with the electron.Answer:B. J.J. Thompson