GIFFORD, Fla. -- A man was wounded in a shooting Friday night at a convenience store in Gifford. The Indian River County Sheriff's Office says they received a call about a shooting in the 4400 block of 34th Drive in Gifford. Deputies located Eric Roberts, 39, with pellet wounds from a shotgun. Detectives determined that Roberts was threatening customers at the store with a knife. A 58-year-old man discharged a .410 caliber shotgun at Roberts. The shooter was located and admitted to firing at Roberts in self defense. No charges are expected to be filed against the shooter at this time.

Can we draw the following conclusion?
roberts got mad so he started threatening people with a knife.

Choose from:
(A). Yes
(B). It's impossible to say
(C). No
(B).