Answer:
subject, topic, subject matter.
matter, issue, question, concern.
idea, concept, thread, motif, trope, keynote, message.
thesis, argument, text.
gist, essence, core, substance, burden, thrust.
Step-by-step explanation:
Plz don't report because it doesn't say in the answer choices, but sorry if this doesn't help, They are the synonyms for theme tho