The correct answer is C. Cause to be astonished; amaze
Step-by-step explanation:
The word "stupefy" is used in the sentence "Magic tricks stupefy most audience members" to describe the reaction of the audience to the magic tricks, suggesting the magic tricks surprised or had a positive effect in all the audience. Additionally, it is explained this word includes a Latin root that means "being stunned" which is a synonym for being amazed or being astonished. This means, the word "stupefy" refers to the action of astonish someone or amaze him/her and thus, the option that shows the meaning of this word is "cause to be astonished; amaze".