Is it possible to return an answer according to the person's responses?

Hi there,

I want, for example to return an answer according to the person's responses. 

Simply put, if a person answers they like apples and they say they live in one city, they will automatically get an answer of people who sell apples in that city.

if they say they like oranges and live in another city, then they will automatically get the answer of people who sell oranges in the other city.

Can JotForm do this?

Yes, jotform can achieve your needs.

If you want to hide/show fields based on your users' response, please follow this guide: https://www.jotform.com/help/316-how-to-show-or-hide-fields-base-on-user-s-answer

If you would like to send emails based on user responses, please refer to this guide: https://www.jotform.com/help/167-how-to-send-email-based-on-user-s-answer

Please give it a try and let us know how it goes.

The question is, can the logic match to predefined answers?

Yes it is possible to achieve this. You can add all the desired questions in form where user can answer the fruit they like and the city they live.

You can add conditions in form to check the user's answer and display another field / text field based on the answer but all the fields should already be there in form. The following guide should help you how to show/hide fields based on user's answer: https://www.jotform.com/help/316-how-to-show-or-hide-fields-base-on-user-s-answer

If you meant to ask something else, please explain your question a bit more in detail with example, and we will take a look.

We will wait for your response.

we have a list of defined answers - and the logic should choose the answer automatically .. from what you are saying, we have to work out all permutations first

Yes, you can list and try the hide/show condition first and let us know if you have any further questions.