[单项选择]The passage suggests which of the following about the recent research mentioned in lines 9-13
A. (A) It has solved one set of problems but has created another.
B. (B) It has overemphasized method at the expense of obtaining interesting results.
C. (C) It has failed to propose practical applications for cold fusion, even if the phenomenon is proven to exist.
D. (D) It has relied upon an experimental method possibly geared toward producing false results.
E. (E) It has provided considerable information on the possibility of cold fusion phenomenon but it has failed to produce innovative experimental apparatus.

[单项选择]The passage suggests which of the following about the increased resistance to harmful root fungi that some Plants infected with mycorrhizal fungi seem to exhibit
A. There are at least three hypotheses that might account for the increase.
B. The plants that show increased resistance also exhibit improved nitrogen fixation.
C. Such increases may be independent of mycorrhizal infection.
D. It is unlikely that a satisfactory explanation can be found to account for the increase.

[单项选择]The passage suggests that which of the following had occurred as a result of education's failure to diminish social inequity

[单项选择]The passage suggests that which of the following is true concerning the probability that a given collision on Mars would eject fragments that will hit the Earth
A. (A) The probability is higher if the impact produces a crater larger than three kilometers.
B. (B) The probability is lower if the impact produces a crater smaller than three kilometers.
C. (C) The probability is decreased when the impact comes from an area of Mars covered by debris.
D. (D) The probability is decreased when the fragments produced by the impact are larger than 10 centimeters.
E. (E) The probability is decreased when the fragments produced by the impact are younger.

[单项选择]The passage suggests that which of the following would be true if volcanic eruptions did not take place
A. (A) The environment would likely contain fewer non-biodegradable pollutants, due to lesser quantities of sulfurous gases and ash clouds.
B. (B) Greenhouse gas effects on rising global temperatures would likely be somewhat less worrisome than those postulated by scientists today.
C. (C) Acid rain produced by heavy industry would likely be more of a problem than it currently is, given the tendency of volcanic eruptions to hasten atmospheric cycles.
D. (D) Global warming effects caused by human activities would be far more substantial than they are today if volcanic cooling effects ceased to take place.
E. (E) The environment would likely be cooler, for the atmosphere would contain fewer sulfurous gases and ash clouds.

[单项选择]The following short passage is mainly about


A. knowledge acquisition research.
B. knowledge-based system development.
C. the conceptual computational structures.
D. the cognitive processes.