Which type of glassware is "TD"?

The correct choice indicates that the glassware labeled as "TD" stands for "to deliver." This designation means that the glassware is designed to deliver a specific volume of liquid accurately when filled to the calibration mark.

Syringes are a form of "TD" glassware because they are commonly used in pharmacies and laboratories for precise measurements and dispensing of medications or solutions. The design of syringes allows for controlled delivery of small volumes, making them an essential tool in various applications.

Other types of glassware typically have different designations. For example, volumetric flasks, which are also calibrated for accuracy, are often labeled as "TC," meaning "to contain." This signifies that while they hold a certain volume when filled to the mark, they may not deliver that precise volume when emptied, due to residual liquid that can remain in the flask. Similarly, graduated cylinders and Erlenmeyer flasks serve different purposes and may not be specifically categorized as "TD" or "to deliver," focusing instead on either measuring volume or mixing solutions.