Answer:
A. He's shocked by the revelation of Wemmick's Walworth life.
Step-by-step explanation:
Jaggers calls Wemmick the "most cunning imposter in all of London" since Jaggers can't help contradicting what Pip said that Wemmick is a sort hearted individual. Since the Wemmick that Jaggers knew is not the same as what Pip depicted him to be. The Wemmick that Jaggers knew is extraordinary. The Wemmick that he knew can frequently be such a figuring individual in his business dealings. That is the reason Jaggers facetiously alluded to him as the most shrewd faker in all of London.