The litmus paper is used as an indicator to determine the pH of a solution, specifically to detect whether a substance is acidic or basic. The color changes observed with litmus paper—red in acidic conditions and blue in basic conditions—are due to the chemical properties of the dyes used in the paper, which react to the presence of hydrogen ions (H⁺) or hydroxide ions (OH⁻) in the solution.
The Benedict's test, on the other hand, is a specific chemical reaction used to detect the presence of reducing sugars, such as glucose. It is not related to the function of litmus paper.
So, in answer to your question, litmus paper acts primarily as an indicator for acidity and basicity, rather than as a chemical reaction like the Benedict test.