hello my apple id has locked but i have only 1 answer from security question..plz help

See this article If your Apple ID is locked or disabled - Apple Support

In the last screen shot enter the answer for that question , if it is showing a different question and you don't know the answer for it , then its better to reset the password through rescue mail .

Rescue mail is added when the Apple ID was initially created , click on that option and in case if you had a rescue mail address and password open it from web mail account ( like gmail or yahoo ) , click on the link , type new password , and verify it and click on save .

In case if you are not having any details be ready with all your details , your call back number , Mac serial number , original invoice copy and contact apple support see these articles Contact Apple for support and service - Apple Support

Contact - Official Apple Support

In the last image answer your current security questions , type the answer for security question and not as Apple ID password .