Definition: In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
Input: Question: The presence of phosphatidylserine on the cell surface indicates: 
 Options:  <1> Cellular senescence <2> Apoptosis <3> Necrosis. <4> Mitosis. <5> Hormone stimulation
