Which tool is used to clean out test tubes?

• A. Test Tube Brush
• B. Stirring Rod
• C. Swab
• D. Transfer Pipet

Answer: (C)

Cleaning inside a test tube requires a tool that can reach and scrub the interior surfaces. A test tube brush is specifically designed for this task: its bristles fit inside the narrow tube and the handle lets you scrub along the walls and bottom to remove residues. A swab, while useful for sampling or spot cleaning, isn’t effective for thoroughly scrubbing the entire interior. A stirring rod is meant for mixing solutions, not cleaning, and a transfer pipet is for moving liquids. So the test tube brush is the appropriate choice for cleaning out test tubes.