Concept:The missing word must express an excessive degree that makes something unsuitable.Explanation:The sentence is: “She wondered if the water was not ___ hot for drinking.”The word “too” means more than is desirable, permissible, or acceptable.“Too hot for drinking” is the correct idiomatic phrase.“Very” and “so” only add emphasis, not the idea of excess.“Much” cannot be used directly before “hot” in this way.Answer:B. too