Which sentence is an example of standard English, with no slang or use of vernacular?

AMountain biking is totally fun.

Eliminate

BMountain biking is one of the coolest sports out there.
CMountain biking is a popular, exciting sport and hobby for many biking enthusiasts.
DMountain biking is a total adrenaline rush for all those who like to hang out and ride their bikes together.

Standard English is a variety of the English language that is accepted as the usual correct form. As opposed to all the Nonstandard English dialects, it is widely used in formal settings, by the governments, the media, schools, and international communication. “Mountain biking is a popular, exciting sport and hobby for many biking enthusiasts” is an example of standard English because it contains words that can be used in formal settings and that can be understood by all English speakers (it does not have any slang or connotations).

The other sentences, on the other hand, are not examples of Standard English because “totally” is a slang used for emphasis, the meaning of the adjective “cool” is subjective and varies and change depending on the group who is using it, plus, it is very informal like “hang out.”