To change your security questions, click on 
This brings you to the Account Settings screen. Click on "Security Questions."
For security reasons, your current security questions and answers are not shown, and you must change all of your security questions and answers, not just one.
You can choose from the following questions:
- In what city did you meet your spouse/significant other?
- What street did you live on in third grade?
- What is your oldest sibling's birthday month and year? (e.g., January 1900)
- What is the middle name of your oldest child?
- What is your oldest sibling's middle name?
- In what city or town did your mother and father meet?
- What was the last name of your third grade teacher?
- What is your maternal grandmother's maiden name?
- In what city does your nearest sibling live?
- What school did you attend for sixth grade?
- What is your spouse's mother's maiden name?
- What is the name of the company of your first job?
- What is your oldest cousin's first and last name?
- In what city or town was your first job?
- What is your favorite author's last name?
- What was your childhood nickname?
When you finish, click Save and you will see a confirmation of the update.