What does extraction, transformation, and loading mean?

What is the best revision of this statement from the body of a cover letter?

Which best describes the tone in these lines "the fish"

Identify the following sentence as simple, compound, complex, or compound-complex. even though most people think of africa as a desert, zimbabwe has a hot, tropical climate, so mangoes, passion fruit, pineapples, and avocados grow well there. a. compound b. simple c. complex d. compound-complex