Step 1: Understanding Project Time and Costs.
When the project time is reduced, typically more resources are employed to accelerate the work, which results in an increase in both direct costs (labor, materials) and indirect costs (overhead, supervision).
Step 2: Conclusion.
Therefore, reducing the project time generally increases both the direct cost and the indirect cost, making option (3) the correct answer.
Final Answer:
\[
\boxed{3. \, \text{Increasing the direct cost and the indirect cost both}}
\]