Brittany is an engineer who purchased a disability insurance policy with coverage that provided for a $3,750 monthly benefit two years ago. Brittany, who was earning $75,000 annually at that time, had a future purchase option (FPO) rider as part of her policy that was guaranteed to 20% of original coverage. Brittany now earns $100,000 annually. What is the maximum additional benefit she could qualify for according to her policy?
a)		$416
b)		$750
c)		$1,250
d)		$2,083