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
True about conversion of monomer to polymer is 
Select and explain. 
A. Density changes from 1.19g/cm3 to 0.9 and volume shrinkage is 21%, B. Density changes from 1.19g/cm3 to 0.9 and volume shrinkage is 7%, C. Density changes from 0.9g/cm3 to 1.19 and volume shrinkage is 21%, D. Density changes from 0.9g/cm3 to 1.19 and volume shrinkage is 7%
C: Density changes from 0.9g/cm3 to 1.19 and volume shrinkage is 21%
Answer: C: Density changes from 0.9g/cm3 to 1.19 and volume shrinkage is 21% 
Explanation: None