The main reason the United States decided to build a canal across Panama instead of Nicaragua was that: the distance to deliver
materials from the United States was shorter. the United States already had control of the land. the land in Panama had more volcanoes. the land and building rights were less expensive
Since the beginning of the twentieth century, the government of the United States has thought that the constructing canal is essential for American military power. However, the French government had initially had a failed attempt in building a canal in Panama.
The French chief engineer on the initial plan was Philippe Bunau-Varilla. It was him who proposed to sell the company's land holdings and all other equipment and infrastructures on the ground already to the United States at a sum that is relatively cheaper. He also argued that unlike Nicaragua, Panama has no volcanoes.
Hence, the correct answer is "the land and building rights were less expensive"