Synonyms are words which have the same or nearly the same meaning in the same language.
Antonyms are words which have opposite meaning in comparison to the other.
Option E)misery is correct as the word misery means a state or feeling of great physical or mental distress or discomfortand the word ecstasy means an overwhelming feeling of great happiness or joyful excitement.
Both the words are opposite of each other.
The other options are not correct as they do not have the opposite meaning to the given word.