Hi Etsuko -
I don't believe that type of complex logic exists at this point within the registration pages (where subsequent responses can change based on previously selected answers), but it's a great idea! I think I have seen some similar ability within surveys premium, but not within registration, but it's worth checking with the Cvent Support Team to be sure.
I think you will probably be able to get what you are looking for by asking the 5 separate questions (example) with some help text:
For the items below, please select a specific company one time only:
1st choice to meet with (and drop down selection)
2nd choice to meet with (and drop down selection)
3rd choice to meet with (and drop down selection)
4th choice to meet with (and drop down selection)
5th choice to meet with (and drop down selection)
And don't forget, you can also use the Question Summary within the Reports section to quickly get to those calculations:

Hope this helps!
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Rebecca Yousif
Senior Administrator, Event Technology
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