Explanation:

Comprehensive Detailed Explanation
In an Azure Cognitive Search knowledge store, you can project enriched content into three main forms:
File projection # For storing binary or unstructured documents (e.g., scanned PDFs, images).
Object projection # For storing JSON objects (hierarchical/unstructured JSON data).
Table projection # For storing structured, tabular results (relational data).
Case 1: JSON data
JSON is already structured/unstructured textual data.
The right projection type for JSON in the knowledge store is Object projection.
Case 2: Scanned data
Scanned PDF/image data is binary file-based content.
The right projection type is File projection, so you can store the original scanned file along with extracted text.
Final Answer (Answer Area)
JSON data: Object projection
Scanned data: File projection
Microsoft References
Azure Cognitive Search knowledge store projections
Object vs File vs Table projections