50. ___
A. They are newer than the formations in most caves.
B. They were formed by sulfuric acid.
C. They have been artificially preserved.
D. They are smaller than those in any other cave.
40. ___
A. Competition in business.
B. Government grants.
C. A type of economic policy.
D. International transportation practices.
41. ___
American industrialists.
B. French economists.
C. International leaders.
D. Civil War veterans.
42. ___
A. The rights of private business owners should be protected.
B. The government shouldn't interfere in private business.
C. Politicians should support industrial growth.
D. Competition among companies should be restricted.
43. ___
A. The impact of enzymes on chemical reactions.
B. The way the body produces enzymes.
C. The structure of enzymes.
D. Types of chemical products created with enzymes.
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