In the following question, a sentence is given in Direct speech. Out of the four alternatives, select the option that best expresses the same sentence in Indirect (reported) speech: He said to Raina, "I cannot marry you now but I shall surely do so next year."

Introduction / Context:
This question deals with reporting a complex statement about future intention and inability. The direct sentence is: He said to Raina, "I cannot marry you now but I shall surely do so next year." The task is to apply the rules of tense backshifting, pronoun change, and time expression change correctly while keeping the promise and contrast intact in Indirect speech.

Given Data / Assumptions:

- Reporting clause: He said to Raina. - Reported clause: "I cannot marry you now but I shall surely do so next year." - Tenses: present modal "cannot", future modal "shall". - Relationship: "I" refers to "he"; "you" refers to Raina. - Time expressions: "now" and "next year".

Concept / Approach:
Because the reporting verb "said" is in the past tense, we normally backshift modals where possible. "Cannot" becomes "could not", and "shall" usually becomes "would". Pronouns must be adjusted: "I" changes to "he"; "you" changes to "her" because Raina is a female object of the verb "marry". Time expressions also change relative to the time of reporting: "now" becomes "then", and "next year" becomes "the following year". The conjunction "that" is used after "told" to introduce the reported clause.

Step-by-Step Solution:
Step 1: Change "said to Raina" to "told Raina" for natural reported speech with an object. Step 2: Introduce the clause with "that". Step 3: Replace "I" with "he" and "you" with "her". Step 4: Change "cannot marry" to "could not marry" due to backshift of "can" to "could". Step 5: Replace "now" with "then" because the time of speaking is in the past. Step 6: Backshift "shall" to "would" and keep "do so" to refer to marrying. Step 7: Change "next year" to "the following year" to reflect the time from the past point of view. Step 8: The complete reported sentence becomes: He told Raina that he could not marry her then but he would surely do so the following year.

Verification / Alternative check:
To verify, convert the Indirect sentence back into Direct speech. From "He told Raina that he could not marry her then but he would surely do so the following year", we reconstruct: He said to Raina, "I cannot marry you now but I shall surely do so next year." All key parts match: inability at the present moment, a promise for the future, and correct participants. The time expressions and modal verbs line up when we adjust for the point of reference.

Why Other Options Are Wrong:
Option A keeps "cannot" instead of "could not", so it fails to backshift the modal and also looks inconsistent with the past reporting verb. Option B awkwardly says "he told her that he could not marry Raina", which suggests that Raina is a third person instead of the listener, creating confusion. Option D changes the meaning by stating "he would not marry her then", which suggests refusal rather than inability, and this is different from "cannot marry you now".

Common Pitfalls:
Candidates often forget to change time expressions such as "now", "tomorrow", or "next year" when reporting statements from the past. They also mix up the meanings of "cannot" versus "will not" or "would not", which changes the nuance from inability to refusal. Another frequent issue is incorrect pronoun reference when the reported sentence involves two people, such as a man speaking to a woman about marrying her. Mapping each pronoun to its correct referent is critical in reported speech questions.

Final Answer:
He told Raina that he could not marry her then but he would surely do so the following year.