From the given options, select the word that is opposite in meaning to -

Culmination

Beginning

The word that is opposite in meaning to culmination is beginning.

• Culmination means the highest or most important point of something.
• Beginning means the first point in a sequence of events.

The other options are synonyms of culmination, so they are not opposite in meaning.

Completion, climax, and conclusion all mean the end of something.

Climax is specifically the highest point of excitement or intensity.