Answer:
A. Global Positioning System (GPS)
Explanation:
The Global Positioning System (GPS) is the most accurate way to find your exact location, virtually anywhere on the planet, thanks for a large network of satellites orbiting the planet and providing location information. That system is also complemented by the cellular towers if you're using a cell phone.
Aerial photography is great, but it will not tell you where you are.
Remote sensing is to gather information from a distance, not relevant to the question here.
The Geographic Information Systems are information systems to give information about the land matched with precise GPS information, used in mining for example, but it's not able to tell you where you are, it's to tell where a gold deposit is however.
The Indian Ocean is the ocean that is east of Africa and west of Australia.