The increase in a person’s body temperature t(t), above 98. 6ºf, can be modeled by the function , where t represents time elapsed. What is the meaning of the horizontal asymptote for this function? the horizontal asymptote of y = 0 means that the person’s temperature will approach 98. 6ºf as time elapses. The horizontal asymptote of y = 0 means that the person’s temperature will approach 0ºf as time elapses. The horizontal asymptote of y = 4 means that the person’s temperature will approach 102. 6ºf as time elapses. The horizontal asymptote of y = 4 means that the person’s temperature will approach 4ºf as time elapses.