What is the value of stress induced in the rod due to impact load?

• A. P/A (1 + (1 + 2AEh/PL)^1/2)
• B. P/A (2 + 2AEh/PL)
• C. P/A (1 + (1 + AEh/PL)^1/2)
• D. P/A ((1 + 2AEh/PL)^1/2)