Question

q. 12 which scientist discovered the electron?
qa rutherford
qb dalton
qc democritus
qd thomson

Explanation:

In 1897, J. J. Thomson discovered the electron through his experiments with cathode - ray tubes. Rutherford is known for the gold - foil experiment and the discovery of the nucleus. Dalton is associated with atomic theory. Democritus was an ancient Greek philosopher who proposed the concept of atoms.

Answer:

D. Thomson