1. In the passage， the author is primarily interested in
（A） suggesting an alternative to an outdated research method
（B） introducing a new research method that calls an accepted theory into question
（C） emphasizing the instability of data gathered from the application of a new scientific method
（D） presenting a theory and describing a new method to test that theory
（E） initiating a debate about a widely accepted theory
2. The author of the passage would be most likely to agree with which of the following statements about the Milankovitch theory？
（A） It is the only possible explanation for the ice ages.
（B） It is too limited to provide a plausible explanation for the ice ages， despite recent research findings.
（C） It cannot be tested and confirmed until further research on volcanic activity is done.
（D） It is one plausible explanation， though not the only one， for the ice ages.
（E） It is not a plausible explanation for the ice ages， although it has opened up promising possibilities for future research.
3. It can be inferred from the passage that the isotope record taken from ocean sediments would be less useful to researchers if which of the following were true？
（A） It indicated that lighter isotopes of oxygen predominated at certain times.
（B） It had far more gaps in its sequence than the record taken from rocks on land.
（C） It indicated that climate shifts did not occur every 100，000 years.
（D） It indicated that the ratios of oxygen 16 and oxygen 18 in ocean water were not consistent with those found in fresh water.
（E） It stretched back for only a million years.
（A） suggesting an alternative to an outdated research method
（B） introducing a new research method that calls an accepted theory into question
（C） emphasizing the instability of data gathered from the application of a new scientific method
（D） presenting a theory and describing a new method to test that theory
（E） initiating a debate about a widely accepted theory
2. The author of the passage would be most likely to agree with which of the following statements about the Milankovitch theory？
（A） It is the only possible explanation for the ice ages.
（B） It is too limited to provide a plausible explanation for the ice ages， despite recent research findings.
（C） It cannot be tested and confirmed until further research on volcanic activity is done.
（D） It is one plausible explanation， though not the only one， for the ice ages.
（E） It is not a plausible explanation for the ice ages， although it has opened up promising possibilities for future research.
3. It can be inferred from the passage that the isotope record taken from ocean sediments would be less useful to researchers if which of the following were true？
（A） It indicated that lighter isotopes of oxygen predominated at certain times.
（B） It had far more gaps in its sequence than the record taken from rocks on land.
（C） It indicated that climate shifts did not occur every 100，000 years.
（D） It indicated that the ratios of oxygen 16 and oxygen 18 in ocean water were not consistent with those found in fresh water.
（E） It stretched back for only a million years.
