Each of two drugs, S and T, greatly reduces the effects of potentially fatal heart attacks if given as soon as possible after the attack begins, but a trial has shown that use of drug T instead of drug S would prevent death in one additional case out of 120. Drug T, however, costs $2, 000 more per treatment than drug S. Ttherefore society is presented with a stark policy decision: whether or not to pay the $240, 000 it would cost to use drug T in order to save one additional patient. Which one of the following is an assumption on which the argument relies? ['Drug S has certain side effects not shared by drug T.', 'After a heart attack, drug T remains relatively effective if given at a time at which drug S is no longer effective.', 'Drug T works significantly faster than drug S.', 'There is no quick, practical, and relatively inexpensive way of telling for any individual case whether drug S will be as effective as drug T.']