Final answer:
Theories play a critical role in assisting practitioners by providing frameworks that inform actions and decisions, which is essential for making informed choices in health interventions and policy development.
Step-by-step explanation:
The purpose of theory in disciplines such as sociology, health, and economics is to offer a systematic way to understand and analyze phenomena. Theories assist practitioners in a variety of ways. Among these, the most pertinent example that highlights how theories can assist practitioners is option C: Inform actions and decisions. This is because theories provide frameworks that help in the understanding of not only the problems at hand but also the potential outcomes of various actions. This understanding is crucial for practitioners who need to make informed actions and decisions regarding health interventions, policy development, and patient care. A good theory simplifies complex issues into their essentials, allowing for clear analysis and facilitating the application of theoretical knowledge to real-world situations to improve health outcomes and policies.