Final answer:
Option 3: D, B, C, A is the correct letter sequence that represents the order of the steps in the request for proposal process.
Step-by-step explanation:
The correct letter sequence that represents the order of the steps in the request for proposal process is Option 3: D, B, C, A.
The request for proposal process typically follows these steps:
- D - Define the needs and requirements of the project.
- B - Research potential suppliers or contractors.
- C - Develop and issue the request for proposal.
- A - Evaluate the proposals and select the best option.
Option 3 reflects the correct order of these steps.