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: It has a single nucleus in central position: 
 Options:  <1> Skeletal muscle fiber. <2> Cardiac muscle fiber. <3> Osteoclast <4> Thrombocyte <5> Erythrocyte
