What is one of the functions of the ICTU?

The function of the ICTU, or Irish Congress of Trade Unions, includes settling disputes between unions. This organization serves as a national coordinating body for trade unions and plays a crucial role in advocating for workers' rights and ensuring solidarity among different unions. When disagreements arise, whether due to conflicting interests or negotiation strategies, the ICTU steps in to mediate and help find resolutions that are satisfactory to all parties involved, thereby fostering unity and cooperation within the labor movement.

The other options relate to functions that are typically the responsibility of individual trade unions rather than the ICTU. For example, workplace promotions and performance appraisals are usually handled at the organizational level by management in relation to their employees, while management of individual trade union funds is a specific operational function of the unions themselves rather than the overarching body like the ICTU.