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: Indicate the net charge of an amino acid with a neutral R group for a pH value below its pI: 
 Options:  <1> Negative net charge. <2> Positive net charge. <3> Without charge. <4> It is necessary to know the exact pH value to answer this question. <5> It is necessary to know the concentration of the amino acid to answer this question.
