The teacher said to the students, “Do not make noise.” Choose the option that best expresses this sentence in indirect (reported) speech.

Introduction:
Direct and indirect speech questions require you to change the form of a quoted sentence while keeping its meaning intact. The original sentence shows a teacher instructing students not to make noise. When we convert this into reported speech, we need to adjust the verb of reporting, remove quotation marks, and choose an appropriate reporting verb like ask, tell, or warn, while keeping the negative command structure correct.

Given Data / Assumptions:

- Direct speech: The teacher said to the students, “Do not make noise.” - Reporting structure: said to the students. - The quoted sentence is a negative imperative, telling students not to do something. - We must choose a reported version that is grammatically correct and natural.

Concept / Approach:
To report an imperative, we usually use a verb like asked, told, or ordered followed by the object and an infinitive phrase. A negative command Do not make noise becomes not to make noise in reported speech. The phrase said to the students typically changes to asked the students or told the students in this context. The simplest, most neutral choice here is asked, because the sentence does not explicitly show anger or threat. Therefore, The teacher asked the students not to make noise is an accurate and grammatically correct reported version.

Step-by-Step Solution:
Step 1: Replace said to with an appropriate reporting verb and object phrase, such as asked the students. Step 2: Remove quotation marks and convert Do not make noise into the infinitive structure not to make noise. Step 3: Join the parts to form The teacher asked the students not to make noise. Step 4: Check that the tense and meaning are preserved: there is still a present instruction not to create noise, reported from the teacher's point of view.

Verification / Alternative check:
Think of similar transformations: The teacher said to the students, “Sit down.” becomes The teacher asked the students to sit down. For a negative command, “Do not talk,” the reported speech is The teacher asked the students not to talk. The structure in this question is parallel, confirming that The teacher asked the students not to make noise is correct. The sentence is clear, concise, and follows standard grammar rules for reporting commands.

Why Other Options Are Wrong:
Option B, The teacher scolded the students, they should not make noise, uses an incorrect sentence structure with a comma splice and adds should, changing the original form. Option C, The teacher warned the students not to make noise, is grammatically acceptable but introduces the idea of a warning, which is stronger than the original neutral said to. Exams usually prefer the most direct equivalent, which is asked. Option D, The teacher told the students that do not make noise, is ungrammatical because the that clause is not correctly formed; it should be that they should not make noise or simply not to make noise.

Common Pitfalls:
Students often ignore the need to use an infinitive for reported commands or forget to change do not to not to. Others try to keep said to instead of choosing a more suitable verb like asked or told. To avoid these mistakes, remember that imperatives normally become to plus base verb in reported speech and that negative imperatives use not to. Practising with many examples of reported commands will make this transformation feel natural.

Final Answer:
The teacher asked the students not to make noise. is the best and most accurate reported speech version.