context: For the third straight season, the number one seeds from both conferences met in the Super Bowl. The Carolina Panthers became one of only ten teams to have completed a regular season with only one loss, and one of only six teams to have acquired a 15–1 record, while the Denver Broncos became one of four teams to have made eight appearances in the Super Bowl. The Broncos made their second Super Bowl appearance in three years, having reached Super Bowl XLVIII, while the Panthers made their second Super Bowl appearance in franchise history, their other appearance being Super Bowl XXXVIII. Coincidentally, both teams were coached by John Fox in their last Super Bowl appearance prior to Super Bowl 50.
question: ఎన్ని జట్లు 15-1 రెగ్యులర్ సీజన్ రికార్డును సాధించగలవు?
answers: six ten ten