A fish can encounter various osmoregulatory problems in different environments. Given the following issues, select the option that correctly describes the osmoregulatory problems among freshwater fish.
P. Loss of water
Q. Salts buildup within the body
R. Osmotic flooding of cells
S. Loss of salts

• A. P and Q
• B. Q and R
• C. R and S
• D. P and S

Answer: (C)