From the following partial code listing, identify the name(s) of event-handler method(s)

that would need to be written. To what object(s) are they wired?

public class Question System.Windows.Forms.Form { : private System.Windows.Forms.Label label1; private private System.Windows.Forms. Text Box txtBxActivity; System.Windows.Forms.CheckBox ckBxSwim; System.Windows.Forms.CheckBox ckBxSnorkel; System.Windows.Forms.TextBox txtBxResult; private private // Colon indicates items missing. private void InitializeComponent() { this.label1 = new System.Windows.Forms.Label(); this.ckBxSwim = new System.Windows.Forms.CheckBox(); this.ckBxSnorkel = new System.Windows.Forms. CheckBox(); this.1stBxEvents. SelectedIndexChanged += new System.EventHandler (this. 1st BxEvents_SelectedIndexChanged);