Explanation:

- Option 1: The application is thereupon numbered and registered as a plaint.

- If A pays the necessary court fees, the application can be treated as a formal plaint.

- This is consistent with the procedure that allows for the continuation of the suit.

- Option 2: The application for leave to sue as a pauper having been made in good faith, and not on the day on which the Court-fees were paid.

- The application was initially in good faith since the intention was to sue as a pauper.

- However, if the fees are paid later, this does not affect the original good-faith application.

- Option 3: Both (A) and (B)

- This option suggests that both procedures are valid following the application and payment.

- It's plausible both processes align with legal procedures independently.

- Option 4: None of these

- This would mean neither procedure is applicable, which isn’t the case based on the above reasoning.

Correct Answer: Option 3 - Both (A) and (B)