During a Professional Baseball Game,a Long Fly Ball Is Hit

During a professional baseball game,a long fly ball is hit down the first base line toward the foul ball pole.If it goes to the right of the pole it will be a foul ball,and if it goes to the left it will be a home run.The umpire making this call will have the most difficulty making the judgment because

A) the umpire will be looking right at the foul pole instead of viewing it from an angle.
B) the human visual perceptual system is simply inefficient at making judgments in cases where the visual stimuli are more than a few feet away.
C) it can be very difficult to distinguish one item from another when it there is overlap between the two.
D) the ball will probably disappear from view whether it goes in front of or behind the foul pole.