In the following question, a sentence is given in direct speech. Select the option that best expresses the same sentence in indirect (reported) speech. My sister said to me, "You did not help me yesterday so I will not help you now."

Introduction / Context:
This item checks the learner ability to convert a direct statement that contains both a past action and a future intention into indirect speech. It involves correct backshifting of tense, suitable change of time expressions such as "yesterday" and "now", and adjustment of pronouns. Such questions are common in English grammar sections of competitive exams because they combine several reported speech rules in one sentence.

Given Data / Assumptions:

• Reporting verb: "said to me" in simple past.
• Direct sentence: My sister said to me, "You did not help me yesterday so I will not help you now."
• Pronouns "you", "me", and "I" refer to the speaker sister and the listener who is the narrator.
• Time expressions: "yesterday" and "now" must be changed from the original moment of speaking to the reporting moment.
• The verb phrase "did not help" is simple past and "will not help" is simple future.

Concept / Approach:
When the reporting verb is in the past tense, verbs in the reported clause usually move one step back in time. Simple past changes to past perfect, and simple future with "will" changes to "would". Time words like "yesterday" change to "the day before", and "now" becomes "then". The second person pronoun "you" changes according to the new subject of the report, which here is "I" from the narrator perspective. Linking words such as "so" remain, but overall word order shifts from quoted speech to normal statement order without question marks or quotation marks.

Step-by-Step Solution:
Step 1: Keep the reporting clause as "My sister said to me" and follow it with the conjunction "that". Step 2: Change "you did not help me" into "I had not helped her". "You" becomes "I" from the narrator viewpoint, and "me" becomes "her". "Did not help" becomes "had not helped" to match the past reporting verb. Step 3: Change the time word "yesterday" to "the day before" in reported speech. Step 4: Convert "so I will not help you now" into "so she would not help me then". "I" becomes "she", "you" becomes "me", "will not help" becomes "would not help", and "now" becomes "then". Step 5: Combine all parts: "My sister said to me that I had not helped her the day before so she would not help me then."

Verification / Alternative check:
Check that the cause and effect relationship is preserved. In the direct sentence, failure to help in the past is the reason for refusal to help in the present. In the reported version, that relationship remains clear. Sequence of tenses is correct and matches standard grammar rules. Pronoun changes correctly reflect who is speaking and who is listening, and time expressions accurately convey that the statement is reported at a later moment.

Why Other Options Are Wrong:
Option B keeps "have not helped" which is present perfect and does not match the past reporting verb. It also keeps "now", which should change to "then". Option C mixes present perfect "have not helped" with "yesterday", which is not appropriate and also mishandles the time word. Option D uses "yesterday" and "now" directly, which is not acceptable in formal indirect speech when the report happens later; both expressions should change to "the day before" and "then".

Common Pitfalls:
Students often forget to adjust both time expressions in a sentence that contains more than one time marker. Another recurring mistake is changing tense only in one clause and ignoring the future tense part. Learners also sometimes leave pronouns unchanged, which can make the meaning confusing in reported speech. A disciplined step-by-step method where you check pronouns, tenses, and time or place expressions separately helps avoid these errors.

Final Answer:
The correct reported sentence is My sister said to me that I had not helped her the day before so she would not help me then.