how do I disable options based on the previous selection?

I have three drop-down menus for each sample shirt; product, col开发者_Python百科our and grade. Not all products are available in all colours and/or grades. I would like to disable the options that are not available based on the users selection.

I've tried using this answer here (using a radio select). Unfortunately, I can't get it to work with an option-selected input.

This is what I'm working on - quartus.ca/select-options.html

Any guidance would be appreciated.

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You need to dynamically clear and re-insert the OPTIONs on every change, based on your own business logic. You cannot simply disable arbitrary items in a <SELECT> .