How does a freshwater bony fish osmoregulate?

1. A Option A: It retains urea in its blood to raise osmotic pressure
2. B Option B: It produces small volumes of concentrated urine
3. C Option C: It produces large volumes of dilute urine and actively absorbs salts through its gills
4. D Option D: It drinks seawater and excretes salts through its gills

Answer checked 11 October 2026 · How we write and check questions