What right do clients have according to ethical guidelines?

Clients have the right to expect effective services as outlined in ethical guidelines. This emphasizes the responsibility of professionals to provide interventions that are evidence-based and lead to meaningful outcomes. Effectiveness is central to the professional's duty to ensure that clients receive quality care that addresses their individual needs.

The expectation of effective services also reinforces the importance of utilizing best practices and staying informed about the latest research and techniques within their field. This aligns with the commitment to promote the welfare and best interests of clients, ensuring they benefit from the services provided.

The other choices, such as the right to choose professionals freely and the right to veto treatment plans, while important considerations, do not specifically address the core ethical requirement for effectiveness in service delivery. Unlimited contact, while advantageous for client support, is also not a mandated right as it may vary based on professional guidelines and the context of the service.