Sometimes yahoo asked you security question for verify to sign in . But it happens at all that we can not remember the security answer. And after your 3 wrong turn of answer, yahoo will block your for 24 hours. So here is the solution if you forget yahoo secret answer. Follow those steps:
1. http://help.yahoo.com/kb/index?page=home&locale=en_US
2. A new window will be in front of you. Then click "quick link locked account"
3. Again a new window will be there. Now click "email a support agent"
4. Now a new form will be come to fill up it & you have to give a new Email-ID(Without Yahoo)
5. Click "Next"
6. After a while it will confirm you to new e-mail id. And within 24 hours again a new email will be come into your new email id ( given at fill up form). Now they will send you a verify link to sign in yahoo.
7. Now here you have to input your "Locked yahoo ID & Password" And make sign in. Here a new box will be come in front of you to verify your new Email ID. Then click "Left Radio Button" & click Next
8. Then again a new box will come to verification code which is already sent you into your New Email ID. Verify the code with it.
9. Then a new box will come. Here you have to put your old password and your new password.
10. Put those information correctly and send it.
Your ID will be verify