Explanation
Correct answer: C.
Choice C is the best answer. The text tells us that lemons—an expensive imported product—feature in Dutch paintings of the period more frequently than dairy products do. Since it’s unlikely lemons were eaten more often than dairy, this fact casts doubt on the theory that these paintings realistically depicted Dutch diets.
Why the other choices are wrong
Choice A
Choice A is incorrect. In fact, the text suggests the opposite: it says that dairy products were a "major component of the Dutch diet," while lemons were an expensive import item, so we can infer that lemons were eaten much more rarely than dairy products.
Choice B
Choice B is incorrect. The passage doesn’t mention painters from other countries, so there’s no basis to make this inference.
Choice D
Choice D is incorrect. In fact, the text suggests that Dutch painters do have reasons for depicting foods other than to show what Dutch people typically ate. For example, lemons in a painting could indicate wealth or prosperity.