"Was the driving pleasant when you vacationed in Beijing last summer"
"No, it ______ for four days when we arrived. So the roads were very muddy."

A．Errors are more likely when a referee keeps close to the ball
B．The farther the referee is from the incident, the more the errors
C．The more slowly the referee runs, the more likely will errors occur
D．Errors are less likely when a referee stays in one spot

A．and
B．but
C．that
D．what