Step 1: Understand the concept:
Staffing starts with estimating manpower requirements. Two tools are used for this: workload analysis and workforce analysis.
Workload analysis finds out how much work there is and how many persons are needed. Workforce analysis finds out how many persons are available.
Step 2: Check the Assertion (A):
A says that workload analysis and workforce analysis are important to understand the manpower requirements.
This is true, because without them the manager cannot say how many people to recruit. So A is true.
Step 3: Check the Reason (R):
R says that it helps the organisation know whether it is overstaffed, understaffed or optimally staffed.
This is also true. If the workload is more than the workforce can handle, the firm is understaffed. If the workforce is more than needed, it is overstaffed. If both match, it is optimal.
Step 4: Check if R explains A:
The reason tells why the two analyses matter: they reveal the staffing position of the firm, and so they show the real manpower requirement.
So R is the correct explanation of A.
Step 5: Why the other options are wrong:
Option (2) says R is not the explanation, but it is the exact explanation.
Option (3) says R is false and option (4) says A is false. Both statements are true, so these two options are wrong.
Final Answer:
Both A and R are true and R explains A, so option (1) is correct.
\[ \boxed{\text{Option (1)}} \]