Automatically populate Input.Text in Adaptive Card

[walzak]

I'm creating an adaptive card to allow a Teams user to create a work item from a Teams chat. 

The process uses the requester's email and Get User Profile (V2) to send notifications that the request is in queue, so I require an email address:

I would like to automatically populate the email field. 

Of the following options, which would be easier: 

Option A:

Make the adaptive card lookup the email address, similar to the To: field in an outlook email? 

Option B: Make the Adaptive card capture the user details of the people in the chat? 

Whichever option you choose, how might I do it?