Correct Answer - Option 3 : than
The correct answer is option 3, i.e., than.
The sentence uses the blank after an adjective, so it must contain a preposition.
Let's see how the given words are used:
Over- (prep) extending directly upwards from. e.g. I saw clouds over the hill.
Although- (conj) in spite of the fact that; even though. e.g. Although the sun was bright, there was still snow.
Than- (prep) introducing the second element in a comparison. e.g. I am taller than Seema.
And- (conj) used to connect similar words, clauses etc. e.g. Apples and oranges.
Here, the sentence is comparing between 'fit words' and 'fine words'.
So, the most appropriate preposition here is 'than', which shows a comparison between them.
Thus, the complete sentence is: Fit words are better than fine ones.