Which of the following sentences from the passage does NOT follow the overall tone of the passage?

This is correct because the overall tone is objective, whereas this sentence uses a pessimistic tone that doesn’t appear in the rest of the text.
"Living in one of the warmest countries on Earth poses many challenges, as its inhabitants need not only to find inventive ways to stay cool, but they also require innovative strategies that allow them to grow their own food." This is incorrect because this sentence has an objective tone, as does the rest of the text.
"Since 1985, Dmitry Ivanov has been researching hydroponic farming systems, a way to grow crops directly in nutrient-rich water." This is incorrect because this sentence has an objective tone, as does the rest of the text.
"Among its many advantages, Dmitry remarks on the fact that hydroponics offers a decrease in water usage in agriculture: to grow 1 kilogram of tomatoes using intensive farming methods requires 400 liters of water, whereas hydroponic methods need only 70 liters." This is incorrect because this sentence has an objective tone, as does the rest of the text.