ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.

A. A man of disreputable nature.

Explanation:

Just by looking at the question and answers, you can determine that the most formal statement is "A. A man of disreputable nature." By the use of the word formal, people tend to think of respectful/professional words/things. The words "shady character," and "snake in the grass," are more of a casual/informal way of describing a "suspicious" person.

do your own work !