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 first morphological sign of human gastrulation is: 
 Options:  <1> Formation of the neural tube. <2> Formation of the primitive line. <3> Implantation. <4> Compaction <5> Ovulation.
