This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
Condensation shrinkage of porcelain during firing depends on: 
Select and explain. 
A. Rate of arriving at firing temperature., B. Uniformity of particle size., C. Shape and size of particle., D. Type of investment used
C: Shape and size of particle.
Answer: C: Shape and size of particle. 
Explanation: Firing shrinkage occurs due to loss of water and densification through sintering. It is about 40% by volume. This can be reduced by proper condensation and firing technique. The higher the firing temperature the greater is the firing shrinkage.