Cathode rays causes an object placed behind a perforated anode to cast a shadow on the screen. This observation shows that the rays
Answer Details
The observation of a shadow cast by an object placed behind a perforated anode when cathode rays are passed through it shows that the rays travel in straight lines. This is because only the areas not blocked by the object can be illuminated on the screen. Therefore, options A, B, and C are incorrect, as none of them are related to the observed phenomenon.