请教几个OG中的逻辑题：

请教几个OG中的逻辑题：

151. Generally scientists enter their field with the goal of doing important new research and accept as their colleagues those with similar motivation. Therefore, when any scientist wins renown as an expounder of science to general audiences, most other scientists conclude that this popularizer should no longer be regarded as a true colleague.
The explanation offered above for the low esteem in which scientific popularizers are held by research scientists assumes that
(A) serious scientific research is not a solitary activity, but relies on active cooperation among a group of colleagues
(B) research scientists tend not to regard as colleagues those scientists whose renown they envy
(C) a scientist can become a famous popularizer without having completed any important research
(D) research scientists believe that those who are well known as popularizers of science are not motivated to do important new research
(E) no important new research can be accessible to or accurately assessed by those who are not
themselves scientists

这个题目到底是什么意思啊？我读了很多遍，都没有理解。哪位可以用中文翻译一下吗？谢了谢了！！！关键是“a true colleague” 怎么理解？

153. Technological improvements and reduced equipment costs have made converting solar energy directly into electricity far more cost-efficient in the last decade. However, the threshold of economic viability for solar power (that is, the price per barrel to which oil would have to rise in order for new solar power plants to be more economical than new oil-fired power plants) is unchanged at thirty-five dollars.
Which of the following, if true, does most to help explain why the increased cost-efficiency of solar power has not decreased its threshold of economic viability?
(A) The cost of oil has fallen dramatically.
(B) The reduction in the cost of solar-power equipment has occurred despite increased raw material costs for that equipment.
(C) Technological changes have increased the efficiency of oil-fired power plants.
(D) Most electricity is generated by coal-fired or nuclear, rather than oil-fired, power plants.
(E) When the price of oil increases, reserves of oil not previously worth exploiting become economically viable.

此题也是没读懂括号中的内容，即：the threshold of economic viability for solar power (that is, the price per barrel to which oil would have to rise in order for new solar power plants to be more economical than new oil-fired power plants)。请牛人们指点一二！