Mark works as a Software Developer for TechBook Inc. He develops an ASP.NET application, named MyApp1, using Visual Studio .NET. MyApp1 contains an ASP.NET page that is used to register new participants to a quiz contest, which is to be held recently in the city of New York. In order to take part in the quiz contest, an applicant must be between the age of fifteen and twenty-five. Mark adds a TextBox control, named txtDateOfBirth, to the page. He wants to ensure that each prospective participant enters his date of birth in txtDateOfBirth. He also wants to verify that prospective participants meet the age requirement. For this, Mark wants to use a custom client script function. He also wants to minimize the number of trips made to the server. Which of the following actions will Mark perform to accomplish the task?

Each correct answer represents a part of the solution. Choose all that apply.