Find the odd number / letters / word from the given alternative:

Broad : Wide
Light : Heavy
Tiny : Small
Big : Large

The answer is C. Tiny : Small.

The other three pairs are antonyms, meaning they have opposite meanings. Broad is the opposite of narrow, light is the opposite of heavy, and big is the opposite of small. However, tiny and small are not antonyms. They are both synonyms, meaning they have the same meaning.

Tiny means very small, while small means not large. So, the pair tiny : small is not an antonym pair, and it is the odd one out in the given set.