What best describes the function of rubber tubing in laboratory practices?

The function of rubber tubing in laboratory practices primarily revolves around its ability to connect different pieces of glassware and equipment. This is particularly useful for transferring liquids or gases between containers, enabling experiments that require the flow or exchange of substances without exposure to the outside environment. Rubber tubing provides a flexible and secure connection, allowing for movement and adjustments that are often necessary in experimental setups.

In contrast, the other options describe functions that are not primarily associated with rubber tubing. While protective gear, such as gloves, is important for safeguarding hands during experiments, this is not the role of rubber tubing. Holding samples is typically achieved using specific laboratory equipment designed for that purpose, such as test tube holders or clamps. Dispensing chemicals accurately generally involves the use of specific tools such as pipettes or syringes rather than the flexible and connecting role of rubber tubing. Thus, the correct answer highlights the primary and unique purpose of rubber tubing in laboratory settings.