40. According to the passage, which of the following is NOT true? (A) Water service line replacement could increase the exposure to lead while the work is proceeding. (B) Medical and public health experts agree that there is no safe level of lead in the human body. (C) Water sampling results can be different depending on the time of day, season, and method of sampling. (D) The most important thing is to look for a certified laboratory to identify lead contamination.