Which street did you live on when you were growing up?
What's the name of your first pet?
In what city was your parent born?
These are standard identity authentication questions that all have to be answered before you get to bring up what you really called about. Certainly, we want measures of security, though it is possible to authenticate the caller other ways.
Voice biometrics is becoming increasingly popular. It's not a complete solution on its own, as all security experts insist single-step authentication are not secure enough for anything you really wish to protect. But it offers the advantage of convenience and likely better security than questions whose answers can often be obtained with some online searches and a view of your Facebook profile.
Read more in Securely Yours: Voice Biometric Authentication Gains Traction
Related: Detecting Fraud With Voice Analytics