Final answer:
The implied idea in "The Bell Rock" is that the location of Bell Rock made construction of the lighthouse challenging and risky.
Step-by-step explanation:
The implied idea in "The Bell Rock" is option D) The location of Bell Rock made construction of the lighthouse challenging and risky.
This idea is supported by the information provided in the passage, as it describes the rock as dangerous and warns ships to stay away from its shoreline. Additionally, the passage mentions that the captain saw the lighthouse at Mosquito Inlet, indicating that it was strategically built to guide ships and ensure their safety.