What is one of the main factors attributed to panama's booming economy?

I think you forgot to give the options along with the question. i am answering the question based on my knowledge and research. "Panama's sole control over the Panama Canal" is one of the main factors attributed to Panama's booming economy. I hope that this is the answer that has come to your help.

Answeris associated with sunny,dry weather;

The answer is d., a mountain.