Q: How to change the answer of securities question?  Tell me please

See the following: If you didn't receive your verification or reset email - Apple Support

If all else fails, use Step 5 in the link.

Forgotten Security Questions/Answers

You need to contact Apple by:

1 - Using this form

Apple - Support -form iTunes Store - Contact Us

2 - Call Apple in your country by getting the number from here:
http://support.apple.com/kb/HE57

1. 3. Contact Apple by:          

Apple ID: Contacting Apple for help with Apple ID account security

For general  information see:

Apple ID: All about Apple ID security questions