Which phrase correctly completes the sentence: "That was __________ movie I have ever watched."?

Explanation

The correct answer is "the worst" because it is the superlative form used to describe something as the lowest quality among all. "Worse" is comparative and requires a comparison between two items. "Most worst" is grammatically incorrect as "worst" is already a superlative. "Bad" is an adjective but does not fit the superlative context. "Worstest" is not a valid English word.