Long-Time Employees of One or More of the "5 B's

Long-time employees of one or more of the "5 B's" (bars, bowling alleys, bingo parlors, betting establishments, and billiard halls) ​

A) have as much as an 18 times greater nicotine concentration than other workers.
B) have an 11 times greater incidence of lung cancer than do other workers.
C) have both the greater concentration and incidence identified in a and b.
D) have neither the greater concentration nor incidence given in a or b.