This sentence contains a colon where a comma is necessary. The phrase "In the past" is an example of an introductory phrase, explaining information necessary to the context of the sentence, but outside of the main sentence, grammatically. These types of phrases must be followed by a comma in order to separate them from the rest of the sentence. The correct answer choice is, "In the past, many civilizations have looked."

This sentence has misplaced the colon. The colon should come after the word "include" since that word marks the end of the first clause. Note that colons combine two clauses when the second one explains or describes something about the first clause. The correct choice is, "market caps on the stock market include: Roundree, Gargle, and Mousecow."

This sentence misuses a colon. Colons are used to join two separate clauses, when the second clause explains the whole- or something about the first clause. Colons should never split up a clause and, therefore, can never come after a preposition (this would split the prepositional phrase). This is a simple sentence, so no extra punctuation is necessary. The correct choice is, "Damian's shares for 600 million dollars."

In this case, the colon is the best option. The first part of the sentence introduces the following list of animals. Therefore, the colon is the best punctuation to separate the related parts of the sentence. Note that a colon can only follow an independent clause, which "These four are my favorite animals" is. Putting a period at the end of that independent clause, however, creates a fragment with the second clause.

This sentence combines two independent clauses without the use of a coordinate conjunction. Furthermore, the second clause explains an element of the first clause (why he was buying a new calculator). The most appropriate punctuation would be a colon after "calculator." The correct answer is, "buy a new calculator: his calculator"

This sentence contains a misuse of a comma. This sentence joins two independent clauses without the use of a coordinate conjunction. In this case, a semicolon (because the two clauses are related) or colon (because the second clause explains an element of the first clause) would be appropriate. Since there is not an option with a semicolon in the correct place; however, the correct answer is, "They decided to restructure the company: the company."

This sentence misuses a colon. Colons are used to combine two clauses when the second clause explains the whole- or something about the first clause. This sentence is a simple sentence, so there is only one clause present. Colons are never just placed before a preposition, unless that preposition begins a new clause (which is not happening here), and they never come after a preposition, as that would split the prepositional phrase. The correct choice is, "plan for the employees to follow in times of chaos."

A semicolon or a comma followed by a conjunction, not a colon, should be used to join the two independent clauses. Colons should follow independent clauses when introducing lists. A colon may be used to introduce an interrupting phrase at the end of a sentence that renames a thing or idea, in this case the "principle."

The colon placed in the middle of the underlined portion of this sentence is incorrect and unnecessary. The sentence actually needs no punctuation in this location in the sentence, and the colon should be removed. This is because colons should only introduce lists that follow independent clauses, and "The novel was immensely confusing to most readers, featuring such complexities as" is not an independent clause (a sentence that can stand on its own). As the only answer choice that makes this change, the correct answer choice is "such complexities as characters with multiple names, expansive time jumps, and a non-linear story structure."

A colon can only follow a grammatically complete, independently valid sentence. The only option that meets this requirement is "The menu includes the following items . . ."