Correct Answer: denounce

Solution : The first option is the correct answer.

The word applaud means to express approval, admiration, or praise, often through enthusiastic clapping or cheering. On the other hand, the antonym denounce entails publicly condemning or criticising or expressing strong disapproval or rejection of someone or something.

The meanings of  the other options are as follows:

• Magnify refers to making something appear larger or more important than it is.
• Command refers to praise or express approval for someone's actions or qualities.
• Approve refers to formally agreeing or expressing agreement, often indicating consent or endorsement.

Therefore, the correct answer is denounce.