________(41)
A.confined  
B.detained       
C.reduced    
D.closed

________(42)
A.so   
B.for     
C.much 
D.such

Why is “ plankton” mentioned in line 16? 
A. To demonstrate the interdependence of different species
B. To emphasize the importance of food resources in preventing mass extinction.
C.To illustrate a comparison between organisms that live on the land and those that live in the ocean
D.To point out that certain species could never become extinct.

The word “demise” in line 12 is closest in meaning to 
A. change               
B. recovery   
C.help        
D.death

Which of the following is NOT mentioned in paragraph 1 as resulting from rapid ecological change? 
A.Temperature changes
B.Availability of food resources
C.Introduction of new species
D.Competition among species

What does the author say in paragraph 1 regarding most species in Earth’s history? 
A.They have remained basically unchanged from their original forms
B.They have been able to adapt to ecological changes.
C.They have caused rapid change in the environment .
D.They are no longer in existence.

The word “ultimately” in line 7 is closest meaning to
A.exceptionally      
B.dramatically 
C.eventually  
D.unfortunately

The word “it” in line 2 refers to:
A.environment     
B. species  
C.extinction       
D.99 percent

________(44)
A.fits     
B.matches       
C.suits   
D.goes with

________(43)
A.suited     
B. appropriate    
C.likely     
D.good