Answer: Choice A)
Take her phone and laptop with her to get something to eat
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Explanation:
It's always a good idea to keep a close watch on your stuff in a public place like an airport. This is for 2 reasons:
So that's why choice A is the best answer here.
Choice B and C are bad ideas, because of the items mentioned above. Choice D could work but Marnie would have to trust that stranger, which may be a very bad idea. Ideally the stranger would be trustworthy, but there's no way of her knowing for sure. So it's better to go on the side of caution and rule out choice D.