Answer :
Final answer:
Sealing building cracks is a mechanical/physical control method, which uses hands-on tactics or devices to remove or exclude pests as part of Integrated Pest Management. Thus option a is correct.
Explanation:
Sealing building cracks and small openings is an example of a mechanical/physical control method of pest management. This method is a form of hands-on strategy or employing simple devices to directly remove or exclude pests from the area, effectively preventing access or removing them if they're already present.
For instance, using tight-fitting screens on windows and doors to prevent pest entry into a home is a mechanical control tactic. This approach is known to be particularly effective when pest populations have not reached high levels and can serve as an integral part of an Integrated Pest Management (IPM) strategy.