A family is prepared to pay up to $600, $500 and $400 for air tickets for the mother, father and daughter so they can travel to another city for a wedding. The airline offers a promotional air fare of $450 per ticket, on condition that at least three tickets are bought. If the family takes up this promotional offer, what consumer surplus will they gain?
- A$100
- B$150
- C$200
- D$250