Key differences in amphibian vs. human heart structure

Steps:

• Recall amphibian heart has 3 chambers (2 atria, 1 ventricle) with partial blood mixing.
• Note human heart has 4 chambers (2 atria, 2 ventricles) for full separation of oxygenated/deoxygenated blood.
• Identify statement 1 as incorrect (e.g., assumes equal chamber count).
• Confirm statements 2 and 3 as correct (e.g., chamber difference and blood flow separation).

Why C is correct:

• Option C selects statements 2 and 3, matching the anatomical law that amphibians have a 3-chambered heart for mixed circulation, unlike the human 4-chambered heart for double circulation.

Why the others are wrong:

• A includes incorrect statement 1.
• B includes incorrect statement 1.
• D includes all, but statement 1 is false.

Not enough information on exact statements, but based on standard biology.

Final answer: C