Efficiency in instructional methods primarily involves:

Efficiency in instructional methods primarily centers on maximizing the use of resources, including time and materials, to achieve desired learning outcomes. Option B, instructing with minimal resources, highlights a key aspect of efficiency in teaching. This approach encourages instructors to create effective learning experiences without relying heavily on extensive materials or equipment, which can lead to streamlined instruction and more focused learning.

By incorporating minimal resources effectively, instructors can foster creativity and adaptability in their teaching methods, allowing for a more engaging learning environment. This method not only saves costs but also encourages learners to think critically and utilize available resources creatively.

While student participation, maximizing time on task, and reducing instructional content are all important elements of effective instruction in their own right, they don't encapsulate the concept of efficiency in the same way. Student participation can enhance learning, but it doesn't inherently relate to efficiency as an instructional method. Maximizing time on task is important for reinforcing learning but is a facet of execution rather than the efficiency of the instructional method itself. Reducing instructional content may streamline lessons but can risk omitting necessary information, ultimately affecting learning quality. Thus, focusing on the use of minimal resources aligns directly with the principle of efficiency in instructional methods.