If a Demand Curve Goes Through the Point P = $Q _ { d }$

If a demand curve goes through the point P = $6 and $Q _ { d }$ = 400, then

A) $6 is the highest price consumers will pay for 400 units.
B) $6 is the lowest price consumers can be charged to induce them to buy 400 units.
C) 400 units are the most consumers will buy if price is $6.
D) consumers will buy more than 400 if price is $6.
E) both a and c