After the semi-colon in the 1st line, the use of prepositional phrase 'at principal office' is incorrect. The correct way of writing the 1st line, the date and venue would be:
The office bearers of the Science society are requested to attend a meeting with the principal.
Date: 17 September, 20XX
Venue: The principal's office.
Hence, option D is the correct way of replacing part (3).
Options A, B and C are incorrect as they are all prepositional phrases.