What Role Do Phosphatases Play in Signal Transduction Pathways

Multiple Choice

What role do phosphatases play in signal transduction pathways?

A) They transfer a phosphate group from one protein in the pathway to the next molecule in the series.
B) They activate protein kinases by phosphorylation.
C) They amplify the second messenger cAMP.
D) They inactivate protein kinases to turn off signal transduction.