Yes but from "times" you can see that this is a test of VERY basic English. I agree with you that Bread is both correct and fits the context better, and I would still choose "eggs" (a worse answer, from the choices given) because I would analyze what the (really stupid) question-writer wanted.
You are right that window exists in that sense but in this case it's clear that the question writers didn't think about it.
For "window" in particular, we rarely say it the way you imply, the whole Internet has just 4 instances of these words after each other:
(you can try 'have' and 'has' for 'had'). But you might be right that the informal sense of "window" that I think you imply (window of time) might be technically the best answer in a different context but absolutely not the answer to pick!
So it actually is a good example of a potentially better answer that you shouldn't pick after analyzing the question!
This is specifically what actually makes it, eggs, objectively wrong -- though it is the choice that will be marked correct and which you, the test-taker should pick, even if you realize it is wrong. Pedantically, it is wrong to say "less eggs" while it is correct to say "less bread" but due to the level of pedantry, you, the test-taker, should prefer to pick the incorrect answer (eggs) over the only actually grammatical answer (bread) - even though this is a test of English.
You have to set aside what is correct and incorrect and decide how educated the test-writer was, and what they might want you to pick, or what they are attempting to test.
This has direct relevance to the article are discussing.