Which of the following produces a $100 daily profit for a cell phone company earning $10 per plan contract?

Opening a new store location with $200 daily operating cost, generating 30 new plans per day
Redesigning website at $50 daily operating cost, generating 10 new plans per day
Creating television commercial at $25 daily operating cost, generating 15 new plans per day
Offering free $10 gift for every new plan, generating 40 new plans per day