67. The idea is to ___________ the frequent incidents of collision to test the strength of the windshields. (A) assemble (B) simulate (C) accumulate (D) forge

21. At one time doctors discouraged taking multivitamins because they believed that multivitamins ________. (A) could not easily be absorbed by the human body (B) were potentially harmful to people’s health (C) were too expensive for daily consumption (D) could not provide any cure for vitamin deficiencies