Which of the following sentences is punctuated correctly?

The sentence that demonstrates proper subject-verb agreement is D. "Physics is a difficult subject to learn." In this sentence, the singular subject "Physics" agrees with the singular verb "is."

Choice B: "Whenever the boys played in the rain, they came home with muddy clothes."

This is a complex sentence. "Whenever the boys played in the rain" is a dependent clause because it cannot stand alone as a complete thought, and "they came home with muddy clothes" is an independent clause because it can stand alone. The sentence does not contain two independent clauses joined by a coordinating conjunction (which would make it a compound sentence).

Choice D: "She wanted to go to the beach after she left work."

This is also a complex sentence. "She wanted to go to the beach" is an independent clause, and "after she left work" is a dependent clause because it cannot stand alone as a complete sentence.

To clarify:

• Complex sentence: Contains an independent clause and at least one dependent clause.
• Compound sentence: Contains two independent clauses joined by a coordinating conjunction (like "and," "but," or "or").

Thus, both B and D are complex sentences, but B is the most accurate answer in many tests as it clearly demonstrates the use of a dependent clause ("Whenever the boys played in the rain") followed by an independent clause.

This sentence is spelled correctly. The other choices have mistakes: "hear" instead of "here," "price" instead of "prize," and "harestyles" instead of "hairstyles."

According to the rules of capitalization, the first letter of a sentence and proper nouns should be capitalized. In option D, "Rocky Mountains" is a proper noun and it is capitalized correctly. Geography is also a proper noun identifying a subject.

In option A, "College" should not be capitalized as it is a common noun.

In option B, it is partly correct however"Western" should be capitalized as it is a proper adjective referring to a specific region.

In option C, "A1 Plumbing Board of Directors" is capitalized correctly, but "range" should not be capitalized as it is a common noun.

Therefore, option D is the correct answer.

A complex-compound sentence has at least two independent clauses and one dependent clause. This sentence correctly combines all three parts.

The sentence "He liked to cook at home, but she preferred to eat at restaurants." correctly uses a compound sentence structure. It consists of two independent clauses "He liked to cook at home" and "she preferred to eat at restaurants" joined by the coordinating conjunction "but".

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.

The Krebs cycle, part of cellular respiration, happens in the mitochondria. Fermentation and glycolysis happen in the cytoplasm, and photosynthesis occurs in plant cells' chloroplasts.

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.

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.