Question

Periodic changes in the shape of Earth's orbit around the sun lead to Milankovitch cycles that create a complex but predictable change in the temperatures of Earth's surface.

• A. lead to Milankovitch cycles that create
• B. leads to Milankovitch cycles creating
• C. led to Milankovitch cycles that had created
• D. has led to Milankovitch cycles that create
• E. lead to Milankovitch cycles, that will create

Hint:

When you see a long sentence, the first thing to check is subject-verb agreement. Find the main subject and its verb, ignoring any prepositional phrases or clauses in between. For scientific statements or general truths, the simple present tense is usually the correct choice.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
This question primarily tests subject-verb agreement and appropriate verb tense for a scientific fact.

Step 2: Detailed Explanation:
Let's analyze the original sentence for grammatical correctness.
1. Main Subject-Verb Agreement: The main subject of the sentence is "Periodic changes," which is plural. The verb is "lead," which is the correct plural form for the present tense. The agreement is correct.
2. Relative Clause Subject-Verb Agreement: The relative clause is "that create..." The pronoun "that" refers to "Milankovitch cycles," which is plural. The verb "create" is the correct plural form. This agreement is also correct.
3. Verb Tense: The sentence describes a general scientific principle that is a recurring and ongoing process. The simple present tense ("lead," "create") is the most appropriate tense for stating such facts.
Since the original sentence (A) is grammatically correct in all these aspects, it is the correct answer. Let's briefly review the errors in the other options:
(B) "leads" is singular and does not agree with the plural subject "changes."
(C) "led" (past tense) and "had created" (past perfect) are incorrect for describing a general, ongoing scientific principle.
(D) "has led" is singular and does not agree with the plural subject "changes."
(E) "will create" (future tense) is incorrect for a general fact. The comma before "that" is also incorrect.

Step 3: Final Answer:
The original underlined portion is grammatically correct. It maintains proper subject-verb agreement and uses the appropriate tense for a scientific fact. Therefore, option (A) is the correct answer.