Explanation:
It's superior vena cava and vena cava
B. It provides information about why certain measurements are made in an experiment
From experience, to be able to have background research helps in the design of an experiment because it would tell you what is being measured in a experiment. Without the background information, my whole class got lost on what to do until my teacher told us what we had to measure and how we could measure the experiment.
Im going to have to go with C. they pass through channels in the cell membrane