Waves that make up the radiation collide with each other so that they add together or cancel each other out.
This is the phenomenon which occurs when two waves meet while traveling along the same medium.
In the double-slit test experiment, bright and dark fringes was observed which was caused by the superposition of overlapping light waves originating from the two slits which is why option A was chosen as the most appropriate choice.
Read more about Interference here https://brainly.com/question/9655287