As an underwriter you may be required to use several high level software and programs. In addition to standard office tools, be prepared to show your skills in job specific tools and other skills that you have (web tools, scripting, programming, etc.). Don't sound over-confident but an answer that exhibits confidence in this scenario is highly appreciated by the recruiting managers. What is important is that you have a conceptual technical knowledge that helps you in solving the problem at hand and communicate it effectively to the stakeholders.
"I am well versed in using SQL and SAP and have the basic knowledge of Netsuit and Microsoft Dynamics along with Excel. I am capable of analysing several complicated cases using these and also of communicating the results to the clients."