Why did it take so much time and effort to build the panama canal?

it was plagued by difficulties;rain,land sliding, escalating costs,fraud,inadequate machinery,and the dread plagues of yellow fever and malaria doomed the project.

It was plagued by difficulties such as rain, land slides, escalating costs, fraud, inadequate machinery, and yellow fever and malaria were running rampant through the workers.

Ibelieve the answer is c also i'm in k12 too