A peninsula is a piece of land that is or almost sorrounded by water. Out of the given options, whereas Philipines, Brazil, and Austria are not surrounded by water. Saudi Arabia is surrounded by water. Therefore, out of the given options, Saudi Arabia is a peninsula.
The nation located on a peninsula from the given options is Saudi Arabia, as it is part of the Arabian Peninsula, surrounded by water on three sides. The other options do not meet the criteria of being on a peninsula. Saudi Arabia's geographic location makes it the correct choice.
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