单选题 The Occupational Safety and Health Administration (OSHA) was established to protect workers from accidents and unsafe conditions on the job. There has actually been an increase in the number of job-related accidents under OSHA. This demonstrates the agency's ineffectiveness.
Which of the following, if true, concerning the period during which the increase occurred, most seriously weakens the argument above?

【正确答案】 C
【答案解析】