Which word best describes something that is 'repugnant'?

The word "repugnant" is used to describe something that is extremely distasteful or unacceptable, often provoking strong feelings of disgust. Therefore, the best description among the choices is "disgusting." This word captures the essence of what it means to experience something that is repugnant, as it reflects an intense negative reaction to an object, behavior, or idea that is offensive or revolting.

The other choices do not align with the meaning of "repugnant." For instance, "delightful" conveys a sense of pleasure and enjoyment, which contrasts starkly with the negative connotation of repugnance. Similarly, "cheerful" suggests happiness and positivity, while "calm" indicates a state of tranquility and peace, none of which relate to the feelings associated with something repugnant. Therefore, "disgusting" is the most fitting descriptor for the word "repugnant."