Mandalee went to a fruit stand with $20 to spend on berries. She bought 1 pint of blueberries for $3.50, and she bought raspberries for $4.00 per pint. If x represents the number of pints of raspberries, which inequality represents the maximum number of pints of raspberries she can buy without spending more than $20? Assume all prices include tax. A: 3.50x+4.00≤20
B: 3.50+4.00x≥20
C: 3.50x+4.00x<20
D: 3.50+4.00x≤20