Joe, an outspoken union advocate working in the shipping department at Frontline Co. for the past 10 years, is transferred to clean out the oil pit. Joe is also paid less for this job. Joe has several allergic reactions to the oil and quits the company due to health reasons. Frontline Co. has: engaged in constructive discharge. exercised lawful management rights. established a closed shop. made a discriminatory decision in violation of the Civil Rights Act