Answer:
B. Respiratory system
Explanation:
You breathe with your lungs, lungs are in the respiratory system
Wait wait is this a real question are you just joking
Answer:
Companion cell is a type of specialized parenchyma cell, which is located in the phloem of the flowering plants.
Each of the companion cell is usually associated with the sieve element. The main function of the companion cell is uncertain but it regulates the activity of sieve tube.
It plays a major role in the loading and unloading of the sugar molecules into the sieve element. As the sieve tubes do not have nucleus and ribosomes so they need companion cell to help in the transportation of sugar molecules.