A Citrix Engineer needs to write a regular expression to treat the URL www.citrix.com as a literal s

A Citrix Engineer needs to write a regular expression to treat the URL www.citrix.com as a literal string.

Which regular e

xpression can the engineer use?

A. www$.citrix$.com

B. [www\]. [citrix\]. [com\]

C. www+.citrix+.com

D. www\.citrix\.com