Step 1: Understanding the Question:
This question tests knowledge of financial analysis in forestry.
Step 2: Detailed Explanation:
The discounting factor is used to determine the present value of future cash flows.
It is used to calculate the present investment required for future returns.
Present returns (A): Not the purpose.
Future returns (B): Not the purpose.
Future investment (D): Not the purpose.
Thus, the correct answer is present investment.
Step 3: Final Answer:
Thus, the discounting factor is used to determine present investment, which corresponds to option (C).
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