Read the passage below and think about the writer's credibility. Do you know people who have their head in the clouds while driving? Scary! People like this look at their phones more than they look at the road! You're going to be roadkill if you don't do something. You can't holler at them to make them stop, they'll wreck for sure you can't even speak up and ask them to let you out. It's a no-brainer: Don't ride with people who text and drive.

What is the BEST description of this writer's credibility and why?

A. The writer is credible because he uses a variety of sentences and correct conventions of standard written English
B. The writer is not credible because he includes informal word choices and colloquialisms.
C. The writer is credible because he uses a formal tone in his word choices and sentence structures.
D. The writer is not credible because he includes errors in standard written English and informal word choices.