Final answer:
If something is infernal, it is extremely unpleasant.
Step-by-step explanation:
If something is infernal, it is extremely unpleasant. The word 'infernal' is often used to describe something that is hellish, dreadful, or torturous. For example, a student might use the word 'infernal' to describe a particularly difficult and frustrating assignment. Therefore, in the given options, if something is 'infernal', it is definitely extremely unpleasant.
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