Explanation:

- Order 12, Rule 2A:

- This Rule states that documents will be deemed admitted if not specifically denied after service of a notice to admit documents.

- Parties must respond to such notices to prevent automatic admission.

- Order 16, Rule 2:

- Pertains to procedure related to summoning and attendance of witnesses.

- Not related to admission of documents.

- Order 4, Rule 13:

- Concerns filing procedures and document handling within that context.

- Does not address admission or denial of documents.

- Order 6, Rule 10:

- Deals with the procedure for striking out pleadings.

- Unrelated to admitting documents by default.

Correct Answer: Order 12, Rule 2A