Answer:
The answer to this question is a).
In the excerpt of “Games at Twilight” by Anita Desai, the best line that suggests that the children have completely forgotten about Ravi is “They have quite forgotten him”. As the story goes on, the reader was let known that a lot of time has passed using the “Evening” and “Twilight”. From afternoon that they started to twilight could be along time for one round of hide and seek.
I would say that a "Scientific article describing the negative effect of school uniforms" would be your best bet because the article contains factual information about how wearing school uniforms deteriorates a child's creativity ( and whatever the article said)!
I hope that this helped. : )