Carnoy's solution contains which combination of ingredients?

• A. Absolute Ethyl Alcohol, Chloroform, Glacial Acetic Acid
• B. Methanol, Xylene, Water
• C. Ethanol, Acetic Acid, Formalin
• D. Alcohol, Chloroform, Sodium Hypochlorite

Answer: (A)

Carnoy's solution is a rapid fixative whose effectiveness comes from combining three agents: absolute ethanol, chloroform, and glacial acetic acid. Ethanol dehydrates and fixes proteins, chloroform aids penetration and lipid removal, and the concentrated acetic acid swells and precipitates nucleoproteins, preserving nuclear detail and chromatin. This specific trio—absolute ethanol, chloroform, and glacial acetic acid—gives the characteristic rapid fixation and strong nuclear preservation that Carnoy's solution is known for. The other options don’t match this composition (they include solvents or fixatives not used in Carnoy’s), so they don’t provide the same fixing action or nuclear detail.