Step 1: Understand development methods.
Employee development involves various methods such as position rotation, on-the-job development, and training through short-term programs.
Step 2: Evaluate the options.
- Position rotation allows employees to gain diverse skills by working in different roles.
- Short-term syllabi provide specific training in a condensed time frame.
- Development on the job ensures that employees learn practical skills while performing their tasks.
Step 3: Conclude.
All of these methods contribute to the overall development of employees.
Final Answer:
\[
\boxed{\text{All of these}}
\]