An instructor is introducing a new concept to a class in the form of a lecture. In the last 10 minutes of the lecture, the instructor notices that learners are looking out the window and shuffling papers. Which of the following describes a principle of effective instruction that the instructor MOST likely overlooked in this situation?

A.
Organized presentations are essential for holding learner interest.

B.
Learners learn best when they are actively involved in the learning process.

C.
New concepts are difficult to introduce in a limited time frame.

D.
Distractions should be minimized to maximize learning.