Answer:
B
Explanation:
because they are moving at the same direction
The basic unit of life is a D. cell.
D is the correct answer because although life is also made up of the other options, in the end, they are all made up of cells. A tissue is a group of specialized cells, and an organ is made up of different tissues. An organ system is a system of organs that work together.
Hope that helped you.
This process is called melting. When a solid melts, it turns into a liquid.