The following is a scheme showing the fate of carbohydrates during digestion in the human alimentary canal. Identify the enzymes acting at stages indicated as A, B, C and D. Choose the correct option from those given: (Karnataka CET 2006)

• A. A = amylase, B = maltase, C = lactase, D = invertase
• B. A = amylase, B = maltase, C = invertase, D = lactase
• C. A = amylase, B = invertase, C = maltase, D = lactase
• D. A = amylase, B = lactase, C = maltase, D = invertase