C isn't
Tomcat, Tomcat is the entire block that contains C and D. Similar for E and
JBoss / WebLogic. You may also want to include Glassfish for completeness.
I would omit Tomcat though. Both JBoss and WebLogic are perfectly capable of processing JSPs and
servlets, so you can omit Tomcat. (In fact, JBoss uses Tomcat internally.)