Which of the following is the correct abbreviation for a liter?

The correct abbreviation for a liter is represented by a lowercase "l." This abbreviation is universally recognized in medical and scientific contexts. Using a single lowercase "l" helps maintain clarity and standardization in measurements, which is crucial in healthcare settings where precision is essential.

Other options may create confusion or are not standard. For instance, "lt" could be misinterpreted in some contexts and is not the accepted abbreviation. "ltrs" is an informal abbreviation that does not follow standard measurement conventions, and "lit" is simply an incomplete form that does not correspond to the established abbreviation. Therefore, the lowercase "l" is the clear and accurate choice in representing liters in a professional setting.