I would like to put the three columns on the separate answer sheet (\AMCnumericOpts{vertical=true}). In the part with the questions, I only want to have two or one column(s).
I could not figure out how to easily set a columnbreak after each question (in the questions part, NOT on the separate answer sheet).

Could you draw a picture with pages of a question sheet that you would like to get?

When preparing a sample file, I managed to get the columns (using multicols twice).

However, the problem with the automatic column break (or column break using a command) is not yet solved. In the example attached, I use \vspace which is not really nice as the number of cm has to be adapted to each question ...

Two details occurred:

1)
On the separate answer sheet, "Answer n:" might be at the bottom of one column and the digits 0 to 9 (\AMCnumericChoices) at the beginning of the next column or page (see attached file).
Is there an easy way to prevent column or page breaks between the title and the digits or could this be implemented in the new version?

2)
Also \AMCnumericChoices: The decimal point and the sign (+/-) are displayed at the bottom (in vertical mode). Can they be placed in the middle/center so that they are better visible? Could the decimal point be displayed on each line (10 times)?

Can you provide your source file?

I use \vspace which is not really nice as the number of cm has to be adapted to each question ...

Perhaps including the questions in a \vbox to 20cm{ ... } or so?

Is there an easy way to prevent column or page breaks between the title and the digits

Not yet I'm afraid.

2) Options should be added to enhance AMCnumericChoices…

here comes the source file ...

Something like that seems to work:

\element{a}{
\vbox to \textheight{\begin{questionmultx}{Beispiel4}
...
\end{questionmultx}
  \vspace*{\fill}
}
}

Thanks for this useful hint, Alexis!