Choose the correct statement regarding proper specimen collection for coagulation testing from the following choices:

a. The tube needed for coagulation testing should be the first tube drawn.
b. It is acceptable to fill the sodium citrate tube halfway in a polycythemic patient for coagulation testing.
c. When drawing blood from a catheter, care must be taken to avoid heparin contamination.
d. Butterfly needles should not be used when drawing coagulation tubes.

Correct Answer: C