What idea is stated explicitly in the text?

The idea that is stated explicitly in the text depends on the specific content of the text you are referring to. However, based on the options you've provided, the most likely explicit statement is "The horse feels sad about his current situation," as this conveys a clear emotion that can be directly expressed in the text.

If you have a particular text in mind that you would like to analyze, please provide more details or context for a more accurate interpretation.