Kyle then types in another URL:What is Kyle attempting here?

Kyle is a security consultant currently working under contract for a large financial firm based in San Francisco. Kyle has been asked by the company to perform any and all tests necessary to ensure that every point of the network is secure. Kyle first performs some passive footprinting. He finds the company’s website which he checks out thoroughly for information. Kyle sets up an account with the company and logs on to their website with his information.
Kyle changes the URL to:
This address produces a Page Cannot be Displayed error. Kyle then types in another URL:
What is Kyle attempting here?

A.
Kyle is trying incremental substitution to navigate to other pages not normally available.

B.
Kyle is using extension walking to gain access to other web pages.

C.
He is using error walking to see what software is being used to host the financial institution’s website.

D.
By changing the address manually, Kyle is attempting ASP poisoning.