Which of the following is a complex sentence?

A complex sentence is one that contains an independent clause and at least one dependent clause.

In Choice C: "Since time was running short, I hurriedly brushed my teeth while breakfast was warming up," we have an independent clause: "I hurriedly brushed my teeth," and a dependent clause: "Since time was running short." The dependent clause cannot stand alone as a complete sentence, so it depends on the independent clause for its meaning. This combination of an independent and dependent clause makes Choice C a complex sentence.

The other choices are not complex sentences because they either lack a dependent clause or do not have the same level of complexity in their structure.

This is because generating ideas is often the first step in the writing process, whether it's brainstorming, outlining, or freewriting. Before any other actions can take place, the writer needs to have a clear sense of what they want to communicate and how they want to structure their writing.

This sentence presents a specific statistic that may not be common knowledge and is not the author's original idea, so it requires a citation to give credit to the source of this information. A citation is needed to show where this statistic came from, who conducted the study, and when it was conducted. Therefore, option C is the correct answer.

A complete sentence must have a subject and a predicate that expresses a complete thought. Option B, "I walked all three dogs around the park this morning," is a complete sentence because it has a subject ("I") and a predicate ("walked all three dogs around the park this morning") that expresses a complete thought.

In the sentence, "The pumpkin crop was incredibly small this year because of excessive rain in the spring and he", the word "incredibly" is an adverb. Adverbs are words that modify verbs, adjectives, or other adverbs. In this case, "incredibly" modifies the adjective "small," indicating the degree or intensity of the smallness of the pumpkin crop.

The language convention violated in the sentence is pronoun-antecedent agreement. The pronoun "you" does not agree in number with its antecedent "a person." It should either be "he or she" or "they" to agree with the singular or plural antecedent.

It follows all the rules of punctuation compared to the rest.

The sentence written correctly is: "The lizard has the ability to alter its coloration to blend in with the foliage." The word "alter" is spelled correctly, and the pronoun "its" is used correctly to show possession. The word "altar" in options B and D is a different word that means a raised platform used for religious or ceremonial purposes, and the word "it's" in option B is a contraction of "it is," which does not make sense in the context of the sentence.

Option B is the correct sentence, which reads "The building's height was exceeded by its width." This sentence employs standard English spelling, where "exceeded" is spelled correctly, and the apostrophe in "it's" is incorrect, as it should be "its" without an apostrophe.

Choice A: In this option, the subject "The boys and girl" is a compound subject that includes both "boys" and "girl." The mistake here lies in the verb "is," which is singular. Since the subject is plural due to the presence of "boys," the correct verb should be "are."

Choice B: This choice correctly follows subject-verb agreement rules. The subject "The boy" is singular, so the verb "come" is appropriately singular. Similarly, for "the girls," which is plural, the verb "come" is used in its plural form.

Choice C: Here, the subject "The boys" and "the girls" are connected by "or," indicating a singular choice. However, the verb "sings" is in the singular form, which is incorrect for plural subjects. To maintain agreement, the correct verb should be "sing."

Choice D: In this option, the compound subject "The boys and girl" is again presented. However, the verb "visits" is singular, not in agreement with the plural subject. To ensure proper subject-verb agreement, the verb "visit" should be used.