Tourism is the industry in the world.
a. fourth-largest
b. largest
c. second-largest
d. third-largest

The best answer would be A

B. largest

People began traveling for pleasure in the late nineteenth century when roads improved, trains could carry passengers long distances, and increased incomes allowed people the time and money to travel. By the twentieth century, people all over the world could travel, and travel and tourism became the largest industry in the world

answer at the divergent plate boundary in the middle of the ocean;