Step 1: Understand George R. Terry's management functions.
George R. Terry identified four key functions of management: planning, organizing, directing, and controlling. These functions are essential for achieving organizational goals.
Step 2: Evaluate the options.
- Terry outlined 4 key functions of management, so the correct answer is (B).
- Other options are incorrect as they do not match Terry's framework for management functions.
Step 3: Conclude.
The correct answer is 4, as per George R. Terry's classification of management functions.
Final Answer:
\[
\boxed{\text{4}}
\]