You build a custom Form Recognizer model.

You receive sample files to use for training the model as shown in the following table.

Which three files can you use to train the model? Each correct answer presents a complete solution. (Choose three.)

NOTE: Each correct selection is worth one point.

A. File1

B. File2

C. File3

D. File4

E. File5

F. File6

Explanation:
Input requirements
Form Recognizer works on input documents that meet these requirements:

Format must be JPG, PNG, PDF (text or scanned), or TIFF. Text-embedded PDFs are best because there’s no possibility of error in character extraction and location.
File size must be less than 50 MB.

Reference:
https://docs.microsoft.com/en-us/azure/cognitive-services/form-recognizer/overview