Final answer:
In the Evacuated Tube System (ETS) order of draw for blood collection, the light blue top tube is usually the first tube to be filled.
Step-by-step explanation:
The subject of this question is related to the correct order of draw for blood collection tubes in a clinical setting, which is a topic in Medicine. When performing venipuncture, the order of draw is critical to prevent cross-contamination of additives between tubes. This tube is used to collect blood samples for various tests, such as blood chemistry and serology. It contains no additives and is used for serum collection. The light blue top tube is typically the first tube to fill in the Evacuated Tube System (ETS) order of draw, especially when coagulation tests are needed. It's important to note that the order may change based on the specific tests ordered and institutional protocols.