Step 1: Understanding the Concept:
This is an application question. We need to apply the logic of the passage to a new, hypothetical scenario. The scenario is about a *successful* private project that eventually becomes inadequate.
Step 2: Key Formula or Approach:
The passage's core argument is that private financing is a flexible, realistic system driven by profit and demand. We need to apply this logic to the new situation.
Step 3: Detailed Explanation:
- The scenario describes a profitable bridge, which means "demand proves great."
- Let's look at what the passage says happens in this situation. Lines 6-8 state: "Such profits can contribute to the financing of more infrastructure if demand proves great enough..."
- The hypothetical scenario perfectly matches this condition: the bridge is profitable (high demand), but it has failed to meet the demands of traffic (more infrastructure is needed).
- According to the passage's logic, the profits from the initial successful project would naturally be used to finance the next stage of development.
- (E) This option is a direct application of the principle stated in lines 6-8. The profits from the successful bridge would be used to finance new infrastructure (e.g., a second bridge or an expansion) to solve the new traffic problem.
- (A), (B), (C), and (D) are all plausible real-world outcomes, but they are not directly supported by the specific logic presented in the passage. The passage's argument is focused on how the profit motive self-regulates and drives further development.
Step 4: Final Answer:
Applying the principle articulated by the author, the profits from a successful project would be the logical source of funding for further infrastructure development when demand warrants it.