In the following question, a sentence is given in Indirect speech. Out of the four alternatives, select the option that correctly expresses the same idea in Direct speech: The doctor advised the patients to give up smoking.

Introduction / Context:
This question checks your understanding of how to convert a sentence from Indirect speech back into Direct speech. The given Indirect sentence is: The doctor advised the patients to give up smoking. You must decide which Direct speech sentence most naturally and accurately leads to this reported form, while preserving the intention of advice and the reference to the patients.

Given Data / Assumptions:

- Reporting verb: advised (past tense, expresses advice). - Indirect structure: advised the patients to give up smoking. - The message is a strong recommendation, not a question or simple statement of fact. - The addressees are "the patients" in plural.

Concept / Approach:
When an Indirect sentence uses a structure like "advised someone to do something", it often comes from a Direct speech sentence using modal verbs such as "should", "must", or sometimes from an imperative form. The nature of the reporting verb "advised" suggests polite but firm recommendation rather than a direct command. Therefore, a sentence like "You should give up smoking" is a very natural source for the reported sentence. The subject "you" refers collectively to the patients, and the modal "should" aligns neatly with the idea of advice.

Step-by-Step Solution:
Step 1: Identify the core idea: the doctor recommends the action of giving up smoking. Step 2: Recognise that "advised the patients to give up smoking" is a typical reporting of "You should give up smoking." Step 3: Reconstruct the Direct speech with the doctor speaking to the patients in the second person plural: "You should give up smoking." Step 4: Add the reporting clause in the correct pattern for Direct speech: The doctor said to the patients, "You should give up smoking." Step 5: Check that this, when reported, becomes: The doctor advised the patients to give up smoking.

Verification / Alternative check:
If we start from option B, "The doctor said to the patients, "You should give up smoking.", and convert it to Indirect speech, we obtain: The doctor advised the patients to give up smoking. This matches the given sentence exactly in meaning. Neither the relationship between speaker and listeners, nor the nature of the advice, nor the action itself changes. Thus option B is fully consistent with the target Indirect form.

Why Other Options Are Wrong:
Option A is in the form of a question starting with "Why do not you", which would usually be reported with a "why" clause, not "advised to". Option C is a direct imperative command "Give up smoking.", which is usually reported as "ordered" or "told" rather than "advised", suggesting a different tone. Option D introduces "I am advising you", which would typically become "said that he was advising" plus an object clause, not the compact "advised the patients to give up smoking".

Common Pitfalls:
Students often treat all transformations from Indirect to Direct speech as purely mechanical and ignore the nuance of the reporting verb. "Advised" implies recommendation, not interrogation or strict command. Another common mistake is ignoring the match between the structure "to give up smoking" and the Direct speech modal "should". Paying attention to the tone of the verb (advised, ordered, requested, suggested) helps you choose or construct the correct Direct speech sentence in exams.

Final Answer:
The doctor said to the patients, "You should give up smoking."