Final answer:
Starbuck's order to Avast Stubb to let a tropical cyclone 'sing' in the rigging refers to a 'hurricane' as the term is used for this kind of storm in the North Atlantic Ocean and the Caribbean Sea. The correct option is b.
Step-by-step explanation:
In the context provided, Starbuck is ordering Avast Stubb to let a tropical cyclone play its part, suggesting the chaos and power of such storms.
Based on the geographical context given in the accompanying materials, when this type of storm occurs in the North Atlantic Ocean or the Caribbean Sea, it is referred to as a hurricane. Hence, the correct answer to the schoolwork question is "b) Hurricane".