Q. The chromogenic substrate of X-gal is:
A. 5-chloro-4-bromo-3indolyl-beta-D-galactoside
B. 5-bromo-4-chloro-3indolyl-beta-D-galactoside
C. 5-chloro-5-bromo-3indolyl-beta-D-galactoside
D. 5-bromo-5-chloro-3indolyl-beta-D-galactoside
Answer: 5-bromo-4-chloro-3indolyl-beta-D-galactoside
