Captcha on Custom Form – Different Settings

I have successfully added the Captcha to one of my custom forms – but is there a way to remove multiplication from this form only? I want to keep this setting (multiplication, addition, subtraction) on all my other forms but only remove multiplication from my custom from only.

The functions I’m calling – to display the form:

cptch_display_captcha_custom()

To validate the form:

cptch_check_custom_form()

https://www.ads-software.com/plugins/captcha/