An employer operates vessels subject to random drug testing requirements under both USCG regulations and another DOT agency's rules. Under 46 CFR §16.230(j), which approach is the employer permitted to use when managing these overlapping requirements?

1. A. The employer must apply the lower of the two agencies' percentage rates to all covered crewmembers to avoid over-testing.
2. B. The employer must obtain a written waiver from the Commandant before combining the two programs.
3. ✓ The employer may establish separate random selection pools for each agency's covered crewmembers, or may test all such crewmembers at the highest percentage rate required by any applicable DOT agency.Correct
4. D. The employer must test all crewmembers at exactly 50 percent regardless of the other agency's rate, because USCG regulations take precedence over other DOT rules.