191.

You are creating an ASP.NET application called ACMEApp that will be used by companies to
quickly create information portals customized to their business. ACMEApp stored commonly
used text strings in application variables for use by the page in your application.
You need your application to initialize these text strings only when the first user accesses the
application. What should you do?

The OnStart event only occurs when the first user starts the
application.
Reference: .NET Framework Class Library, ServiceBase Class [C#]
Incorrect Answers
2: The HttpApplication.BeginRequest event occurs
as the first event in the HTTP pipeline chain of
execution when ASP.NET responds to a request.
3: This would set the values every time a new
session is started.
4, 5: We should use the OnStart event handler of the application, not the Page.Load event handler.