5t What is the horizontal asymptote for this function? De A drug is injected into a patient and the concentration of the drug is monitored. The drug's concentration, C(t), in milligrams after t hours is modeled by C(t)=- means in practical terms. 212-2 OA. y=1.25; After 1.25 hours, the concentration of the drug is at its greatest. OB. y=2.50; 2.50 is the final amount, in milligrams, of the drug that will be left in the patient's bloodstream. OC. y=2.50; After 2.50 hours, the concentration of the drug is at its greatest. D. y=0; 0 is the final amount, in miligrams, of the drug that will be left in the patient's bloodstream.