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Apply: embryology and evolution


Read the following statements. Then, answer the question below.
  • Human embryos have structures called notochords. The notochord develops into part of the backbone as the embryo grows.
  • Lamprey embryos also have notochords. In lampreys, notochords are found in adults, too.
  • Sea stars do not have notochords at any stage of development.
Based on this information, which evolutionary tree correctly shows the relationship between humans, lampreys, and sea stars?
Choose 1 answer: