Provide an antonym for "difficult".

An antonym for "difficult" is "easy." The word "difficult" describes something that requires a lot of effort, skill, or determination to accomplish. In contrast, "easy" refers to something that can be done without much effort or that is simple to understand or accomplish. This direct opposition in meaning makes "easy" the appropriate antonym in this context, as it conveys a lack of complexity or challenge, highlighting the ease with which a task can be performed.

The other options convey varying degrees of challenge. "Complex" suggests that something has many parts or is intricate, which can imply difficulty. "Hard" is similar to "difficult" in that it suggests a high level of challenge. "Challenging," while somewhat synonymous with difficulty, also implies a demand for skill or effort, rather than contrasting with "difficult." Thus, none of these alternatives serve as a true antonym.