(28) 
A.when                      
B.and                          
C.until                        
D.while

(20) 
A.make
B.persuade
C.allow
D.decide

(21) 
A.of
B.with
C.to
D.from

From the passage, it can be inferred that to solve our energy problems                    .
A.a combination of conservation and invention will be needed
B.we will have to stop using many of our modern conveniences
C.scientists will have to find ways to increase our supplies of coal, oil, and gas
D.scientists will have to find one major source of nonpolluting energy

It can be inferred from the passage that                          .
A.many alternative energy sources are environmentally hazardous
B.solar and wind power are not promising for the future
C.most alternative energy sources have proven to be impractical
D.nuclear power solves one problem while creating others

(10) 
A.beautiful                 
B.gorgeous                 
C.lovely                     
D.charming

(8) 
A.cost                         
B.charge                     
C.average                   
D.expense

(4) 
A.with                                    
B.to                            
C.for                           
D.at

(26) 
A.protection               
B.guard                      
C.intention                 
D.defense

(22) 
A.method                   
B.process                    
C.procedure              
D.route