Answer:
Option(c)
He sent a cathode ray between electrically charged metal plates
Step-by-step explanation:
In 1897, physicis JJ Thomson experimented with a device called CRT(cathode ray tube) in which a current passed through gases at a low pressure. A CRT(cathode ray tube) comprises of a sealed glass-duct fitted with electrodes at both ends of the metal disks.
Then the electrodes are connected to an electricity source. One electrode, known as anode, will be charged positively while the other electrode, referred as cathode, will be charged negatively. A light beam passes from the cathode to the anode which is called as the cathode ray.