I am trying to anchor objects on different layers is this possible?

Just to recap what your options are to lay it out and see what you would like to proceed with

An option - but probably not ideal

Group the master question with both the print and digital answers.
Keep all grouped objects on the same layer but control their visibility using layer options.

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Use Object Layer Options (for placed PSDs) or Conditional Text (if the text approach works) to toggle between digital and print elements.

This is an example of how it works - it could be an option

https://www.trainingconnection.com/indesign/lessons/conditional-text.php

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@m1b I think recently demonstrated power of script labels and probably correct me on this approach if it's possible

Scripting and Hidden Anchors
Anchor an empty text frame (a "blank" object) to the question.
In the Window>Utilities go to Script Labels this way you can insert a description --- then give the answer frames a label matching this anchor.

Then a script to reposition answers to match the anchor locations when needed.

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Alternate Layouts - as per @Barb Binder 
Create an Alternate Layout for digital and print versions.
Link corresponding text frames between the two layouts so they update together.

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Unfortunately, there’s no built-in way to anchor across layers, but scripting or alternate layouts would likely be the best workaround.

Hi @JH-Wendy:

Perhaps I made a leap here—so please correct me if I'm wrong—but I'm assuming you want to print the print version, and view the interactive version online? And are looking for a way to manage both versions with minimal stress?

If yes, then in addition to what I already mentioned, if you use alternate layouts, you can print the print alternate layout, and export the digital alternate layout to PDF or Publish Online. They are just page ranges within the same file. 

Again, if you have any questions, @JH-Wendy , just ask!

~Barb

Hi @JH-Wendy:

Working within InDesign's feature set, no, you can't anchor between layers. If you have an image on one layer and anchor it to text on another layer, the image will jump itself to the text layer. 

But you are trying to create a multi-version document and there are a few ways to approach it that stay within the feature set: layers, conditional text and alternative layouts.

• So layers are out, obviously.
• Conditonal text doesn't seem like the best approach (see the bottom of this page: https://helpx.adobe.com/indesign/using/editing-text.html). It involves setting up version tags and hiding/showing them. You could certainly play with it, but I'd lean towards an Alternate Layout. (See the bottom of this page: https://helpx.adobe.com/indesign/using/alternate-layouts-liquid-layouts.html).
• An alternate layout creates a different version of a document, within the same file. You can link them together so that they start out the same, but then you can add your interactive features to the digital version. They are both in one file so fairly easy to manage. For example,

I'd start there and then come back if you have additional questions. We are always happy to help.

~Barb

Anchored objects can't be moved to a different layer.

But it can be easily automated - you would have to Anchor/InLine a "blank" object - Rectangle or TextFrame - set a unique label to it - then create your "answer" object - as a group or whatever - then set the same unique label to it.

Then, a custom tool would load info about the location of all the Anchored/InLined "blanks" and move correct "answers" to the correct places.