You are customizing a Windows Form. When the user clicks any button, you want the application to log information about the user’s actions by calling a method with the following signature.

public void ctl_Click(object sender, EventArgs e)

You want the form to invoke this method when any Button control is clicked and only when a Button control is clicked. You need to modify the form to invoke this method without interfering with the existing operations of the application. What should you do?

A.
Add the following code to the form initialization.
foreach (Control ctl in this.Controls) {
if (ctl is Button) {
ct1.Click += new EventHandler(ct1_Click);
}
}

B.
Add the following code to the form initialization.
this.Click += new EventHandler(ct1_Click);

C.
Use the Properties dialog box to set the Click event for each Button control on the form to the ctl_Click method.

D.
Use the Properties dialog box to set the Click event of the form to the ctl_Click method.