Question: I started a Yahoo! mail account a while ago. This was meant to be just a throwaway/spam email account. However, because it was easy to pass around, I ended up depending on it quite heavily. 

Since I didn't pay attention while filling the account creation form I am wondering if it is possible/how to change your Secret Question's answer.

Answer: 
I no longer see a Secret Question for you to answer in order to get a password changed. They now verify it is you by using a secondary email address to send you a code or they will text you a code to your phone number to verify it is you. Those are both in the upper right of the screen under the gear and then account info. From there you go to account security. From here you can add a phone number to which you can receive text messages. If you chose you can also add a secondary email so you can get verified this way as well.
1. Go to Yahoo Mail. Visit the Yahoo Mail website using any web browser on your computer.
2. Sign In. Enter your Yahoo ID or username and password in the fields provided. Click the “Sign In” button to access your account.
3. Go to Account Info. Click the gear button on the top right corner of the page to display a menu. Select “Account Info” from here.
4. A new window or tab will open displaying your profile and account page. Your personal information are here, together with the account and security settings for your Yahoo account.
5. Update your password-reset info. Scroll to the “Sign-In and Security” section of the page, and click the “Update password-reset info” link from the options under the section.
6. View your current security questions. Another page will load displaying your current password reset options and info. Scroll down to the “Secret Questions” section to see your current two security questions.
7. You won’t see your answers to your two questions for your own security and privacy.
8. Change your questions and answers. Right under the questions is a “Change questions and answers” link. Click on it, and the two questions above it will change to drop-down lists containing several options for your security questions.
9. Set Secret Question 1. Click the drop-down list for Secret Question 1. Scroll through the list of questions, and click the one you’d like to use. Right under it is a text box. Input your answer to your first question.
10. Set Secret Question 2. Click the dropdown list for Secret Question 2. Scroll through the list of questions, and click the one you’d like to use. Right under it is a text box. Input your answer to your second question.
11. Save. Right under the questions is a “Save” link. Click on it. Your two questions and their corresponding answers will be saved and recorded by Yahoo.
12. You’ve now reset and changed your security questions. You may go back to your main window or tab for Yahoo Mail.