Question

from his experiments, j. j. thomson concluded that
cathode ray particles can move at very fast speeds.
cathode ray particles can be moved by electric current.
atoms contain small positively charged particles that are called protons.
atoms contain small negatively charged particles that are called electrons.

Explanation:

J. J. Thomson's cathode - ray tube experiments led to the discovery of electrons, which are negatively - charged subatomic particles. He showed that cathode rays were made up of these negatively charged particles, thus concluding that atoms contain electrons.

Answer:

D. atoms contain small negatively charged particles that are called electrons.