You can change the security questions using the 'ANT Mobi' mobile trading app from its Settings menu.
Once you login using your Client Id and Password, you can go to the settings menu and select at least 5 different security questions. Upon selecting questions, a text box will appear where you can type the answers and click on save. Every time you try to log in, the system will randomly ask you any two of the five questions selected by you.
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