Answer:
D. 500 L
Explanation:
Choice A (5 ml) is basically a teaspoon. A bathtub can most definitely hold much more then one teaspoon of water.
Choice B (500 ml) is about 17 ounces. Which is basically the amount of water in a normal water bottle. A bathtub can hold more then the amount of water in one water bottle.
Choice C (50 cl) is a little bit more then 2 cups of water. I believe a normal bathtub can hold about 1280 cups of water.
That rules out choices A, B, and C. By process of elimination, we can tell choice D is the answer. But let's just take a look at D.
Choice D (500 L) is about 132 gallons. This is the most plausible one, although some bathtubs don't hold as much water as that, it still is the best estimate of the capacity of a bath tub. \
Hope that helped!