What are the different types of tubes used for blood collection in clinical biochemistry?

I- Tubes without anticoagulant are used to collect serum.
II- Tubes with silica as a coagulation activator are used to accelerate the coagulation process.
III- Tubes with thrombin are used to obtain serum in several minutes and are mainly used in urgent analyses.
IV- Tubes with lithium heparin are the preferred plasma sample for most biochemistry tests.
a) Only I and II are correct.
b) Only III and IV are correct.
c) All statements are correct.
d) None of the statements are correct.