Correct Answer: B

Rationale: In the context provided, the word 'propagated' indicates that Xavier conveyed or expressed his belief to his friends. 'Expressed' is the most suitable synonym here as it aligns with the idea of communicating a belief clearly. The other options, 'shouted,' 'persuaded,' and 'whispered,' do not capture the essence of spreading or communicating an idea, making them incorrect choices.

Correct Answer: D

Rationale: The word 'disconfirmed' can be understood by breaking down 'disconfirm,' where 'dis' indicates 'not' and 'confirm' means 'to prove.' Therefore, 'disconfirmed' means 'not proven,' which aligns with the meaning of 'disproven.' In the given passage, it is mentioned that evidence can disprove a hypothesis, not necessarily prove it. This supports the synonymity between 'disconfirmed' and 'disproven.' Choice A ('proven') is incorrect because 'proven' is the opposite of 'disconfirmed.' Choice B ('dissipated') is incorrect as it means to disappear or scatter, not related to disproving a hypothesis. Choice C ('distilled') is incorrect as it means to purify a liquid through heating and cooling, not related to proving or disproving hypotheses.

Correct Answer: D

Rationale: Based on the information provided in the extract, it is evident that despite the United States spending a substantial amount on education, it does not translate to top performance in standardized math tests. Countries spending less outperformed the United States, indicating that spending more money does not guarantee success on standardized tests. Choice A is incorrect because the extract does not specify benefits beyond tests. Choice B is incorrect as the extract does not explicitly state that the US education system is corrupt and broken. Choice C is incorrect as the extract talks about the performance on standardized math tests rather than American proficiency in general.

Correct Answer: D

Rationale: The best guide for Raul would be 'Who Built the Great Pyramids?' as it focuses on the construction of the pyramids, providing detailed research on the topic. Choices A, B, and C are less relevant as they do not specifically address the construction of the pyramids. Choice A is about Giza in general, Choice B is a biography, and Choice C is about hieroglyphics, none of which directly relate to the construction of the pyramids.

Correct Answer: D

Rationale: An automobile with eighteen wheels contradicts the hypothesis that 'All automobiles have only four wheels.' This contradiction reduces the probability that the hypothesis is true. The hypothesis is not proven by the presence of an eighteen-wheel automobile, nor does it raise the probability of the hypothesis being true. Instead, it directly challenges the hypothesis, leading to a decrease in its probability of being correct.