B. <span>The thesis statement is the answer to the research question</span>
Answer:
The main difference between sieve tubes and companion cells is that sieve tubes are the long, narrow, pointed tubes present in the phloem of angiosperms whereas companion cells are attached to the sieve tubes, regulating the activity of sieve tubes.
<span>So that the cells can function correctly. </span>
Answer:
mechanical waves
Explanation:
They require a medium to travel through.