question: What is the main alteration in an endosymbiont when it adapts to a host ?
answer: drastic reduction in its genome size
turker_answer: The main alteration in an endosymbiont when it adapts to a host is the drastic reduction in its genome size .
rule-based: The main alteration in an endosymbiont when it adapts to a host is drastic reduction in its genome size .