Final answer:
The green-top tube is not suitable for a CBC as it contains a heparin anticoagulant. A new sample using a different anticoagulant tube is required.
Step-by-step explanation:
The green-top tube is not suitable for a complete blood count (CBC) because it contains a heparin anticoagulant, which can interfere with the CBC results. A new sample is required using a different anticoagulant tube, such as an EDTA tube, which is commonly used for CBC. It's important to notify the physician about the need for a different anticoagulant tube to ensure accurate CBC results.