This question asks you to pick the answer choice which is answered by the passage. This is an odd phrasing for a question. But, the best way to answer it will simply be to look at each answer choice in turn and then see if you can find the answer to that question in the passage.
Answer (A) is incorrect. The Brazilian Amazon region is discussed in the second paragraph but there is no mention of a percentage.
Answer (B) is incorrect. The passage tells us that plantations are made to produce wood and wood pulp (line 47-50), but does not discuss how many products are made from these materials.
Answer (C) is correct. The passage tells us that trees produce oxygen through photosynthesis (line 22). The use of the term plant instead of tree in the answer choice is designed to throw you off. This is a moment where a small bit of outside knowledge (aka that trees are plants and all plants photosynthesize) can be brought in to help you. When you have an answer choice like this that switches up the terminology a bit, it's best to flag it and then eliminate all other answer choices before choosing it.
Answer (D) is incorrect. There is no discussion of helping forests produce more oxygen in the passage.
Answer (E) is incorrect. The passage tells us the Brazilian Amazon absorbs "so much" carbon dioxide that some call it the lungs of the earth (lines 16-21). So, while we know the Amazon (a tropical rain forest) absorbs a lot of carbon dioxide, we have no information about tropical rain forest trees in comparison to other vegetation.
