I think it is sun quacks. It is based on expert judgement.<span />
<span>The answer is B. Mesoderm.
During gastrulation three layers form. Ectoderm, mesoderm, and endoderm. Mesoderm is the middle layer and from that layer a multitude of tissues and organs develop. The mesoderm develops into connective tissues like cartlage, bone, blood, and blood vessels. The mesoderm can also develop into muscle types like cardiac, skeletal, and smooth.</span>
Answer:
Vague, but I think you are talking about duplication or mitosis
Explanation:
Mitosis is duplicating DNA to make two geneticly identical daugher cells
Duplications is just unwinding the DNA to make a second copy