Final answer:
The boldfaced clauses in the sentences are identified as one relative clause, two adverbial clauses, one independent clause, and one noun clause.
Step-by-step explanation:
To identify the type of clause boldfaced in each sentence, we need to look at the function of the clause within the sentence. Here are the types for each boldfaced clause:
- World War II, (which was the deadliest war in history), took the lives of roughly 60 million soldiers and civilians. - relative clause
- The United States remained neutral (until the Japanese bombed Pearl Harbor on December 7, 1941.) - adverbial clause
- The most significant loss from the bombing occurred (when a bomb hit the USS Arizona, detonating the ammunition magazines and causing the ship to explode.) - adverbial clause
- (The following day, the United States declared war on Japan), which prompted Germany and Italy to declare war on the United States. - independent clause
- Great Britain had already promised (that it would immediately declare war on Japan if Japan) launched an attack on the United States. - noun clause