Answer:
Imma just go with D, so u just go with D as well
Explanation:
Answer: The nervous system
Explanation:
The first part of the embryo to develop is the neural tube, which will become the spinal cord and brain. As the nervous system starts to develop, the tiny heart starts to pump blood, and other parts of the body—such as the digestive tract and backbone—begin to emerge.
It is either A or B because constructivism is building together
False blood flows to pick up oxygen not carbon dioxide