Dr Smith, a Veterinarian, Has Hired Carlos as an Assistant

Dr. Smith, a veterinarian, has hired Carlos as an assistant. On Carlos's first day at work, Dr. Smith shows him the technique of holding a cat for vaccinations. First, Dr. Smith describes the technique, and then he demonstrates the process of vaccination. Later he asks Carlos to hold the cat and corrects his mistakes. This is an example of_____.

A) cross-training
B) e-learning
C) simulation-based learning
D) on-the-job training