Malaysia's National Fruit?

Is there such a thing? Who chooses it?

The national flower was selected by the First Prime Minister, so that is a valid selection.

Wikipedia says "rambutan" while says.com says "papaya". Who decided on that and when?

I would probably go with "durian" or "rambutan".. but then again no country claims exclusive rights over tropical fruits. Surely these fruits exist in other countries as well, unless you refer to the unique durian variants that Malaysians have genetically modified 👻