Re-assigning a variable to itself is a defect as it has no actual effect and indicates meaning to do something else. It usually means that:
public class Choice {
private bool selected;
public void MakeChoice(bool selected)
{
selected = selected; // Noncompliant
}
}
public class Choice {
private bool selected;
public void MakeChoice(bool selected)
{
this.selected = selected; // Compliant
}
}