Some people indulge in loud vulgar talk.

The correct answer is A. simple.

The word “simple” means “not complicated or elaborate.” Loud vulgar talk is often used by people who are trying to be funny or to impress others, but it is actually a sign of a lack of intelligence and sophistication. People who indulge in loud vulgar talk are often trying to cover up their own insecurities or to make themselves feel better by putting others down.

The other options are incorrect because they do not accurately describe the behavior of people who indulge in loud vulgar talk.

• Option B, “restrained,” means “controlled or limited.” People who indulge in loud vulgar talk are not controlled or limited in their speech.
• Option C, “graceful,” means “having or showing elegance and ease of movement.” People who indulge in loud vulgar talk are not elegant or graceful in their speech.
• Option D, “refined,” means “having or showing good taste and culture.” People who indulge in loud vulgar talk do not have good taste or culture.