Final answer:
A light blue topped tube containing sodium citrate is used for Prothrombin Time (PT) and Partial Thromboplastin Time (PTT) tests, which are coagulation studies.
Step-by-step explanation:
The light blue topped sodium citrate tube is commonly used for coagulation studies, which include tests such as the Prothrombin Time (PT) and Partial Thromboplastin Time (PTT). The sodium citrate acts as an anticoagulant by binding to calcium ions in the blood, preventing clot formation, which is necessary for accurate coagulation testing. Therefore, the correct answer to the question is b. Prothrombin Time (PT) and c. Partial Thromboplastin Time (PTT).