What adjective describes the plumbing profession as mentioned by the man?

The adjective that best describes the plumbing profession, as mentioned by the man, is "highly." This term indicates a degree of expertise and skill required in the plumbing field. It suggests that plumbing is not just a simple or straightforward job; instead, it demands a significant level of training, knowledge, and proficiency to perform tasks effectively and safely.

The use of "highly" also often conveys respect for the profession, acknowledging the complexity involved in plumbing tasks, such as diagnosing issues, understanding systems, and ensuring compliance with safety regulations. This context underscores the notion that successful plumbers are well-trained professionals rather than individuals in a basic or unskilled role.