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A. Some of the stereotypes you may have heard about Americans are not true
B. You should not believe the stereotypes you may have heard about Americans
C. None of the stereotypes you may have heard about Americans should be believed
D. None of the stereotypes you may have heard about Americans should not be believed

A. throwing stones often caused injuries
B. throwing stones was not fun
C. games with stones did not have rules
D. rocks were too heavy to throw