Step 1: Understanding the question.
The question asks about the number of types of planning according to G. R. Terry. According to his framework, planning is categorized into 6 types.
Step 2: Analyzing the options.
(A) 8: Incorrect. G. R. Terry defined planning into 6 types.
(B) 6: Correct. G. R. Terry categorized planning into 6 types.
(C) 4: Incorrect. Terry's classification is based on 6 types of planning.
(D) 2: Incorrect. There are more than 2 types as per Terry.
Step 3: Conclusion.
The correct answer is (B) 6 as per G. R. Terry's classification of types of planning.