In the following question, a sentence is given in direct speech. Select the option that best expresses the same sentence in indirect (reported) speech. He said, "I will go to Mumbai someday next month."

Introduction / Context:
This question focuses on reporting a future intention that is expressed with "will". The direct sentence talks about a future plan relative to the original speaking time. When we convert this into indirect speech with a past reporting verb, we must backshift the future tense and adjust the time expression "next month". Such items test understanding of tense sequence and time phrase changes in reported speech.

Given Data / Assumptions:

• Reporting verb: "said" in simple past.
• Direct speech: "I will go to Mumbai someday next month."
• Pronoun "I" refers to "he" in the reported version.
• Verb "will go" expresses a future plan.
• Time expression: "next month" must be adapted to indirect speech.

Concept / Approach:
In reported speech, when the reporting verb is in the past, the simple future with "will" usually changes to "would". Time words and phrases must be changed to match the point of view of the reporter. The phrase "next month" becomes "the following month". Pronouns must shift from first person to third person according to the new subject of the sentence. The main aim is to express the same future intention from a position in the past, without changing the planned action itself.

Step-by-Step Solution:
Step 1: Begin with the reporting clause "He said that". Step 2: Change the pronoun "I" to "he", because the speaker is now referred to in third person. Step 3: Convert "will go" to "would go" to backshift the simple future to a future in the past. Step 4: Retain "to Mumbai someday" because the place and the adverb "someday" do not need form change. Step 5: Change the time phrase "next month" to "the following month" to suit reported speech from a later time point. Step 6: Combine the parts into "He said that he would go to Mumbai someday the following month."

Verification / Alternative check:
Check that the action of going to Mumbai is still in the future relative to the time when he spoke, but from the reporting point of view it is expressed as a future in the past. "Would go" correctly carries this meaning. The time expression "the following month" still refers to one month after the original speaking time. The reported version has no quotation marks and uses the conjunction "that", which is standard in formal indirect speech.

Why Other Options Are Wrong:
Option B is wrong because it mixes the present "says" with "would go", which is not logical in this context. Option C keeps "will go", which fails to backshift the future tense after a past reporting verb. Option D again uses "says" with "will go", which would only be correct if the report were truly in the present, but the original sentence clearly treats "said" as a past action in the test pattern.

Common Pitfalls:
A common error is to forget to change "will" to "would" when the reporting verb is in the past. Some learners also forget to adjust the time phrase, leaving "next month" unchanged in indirect speech, which can cause confusion about when the action is supposed to happen. Another issue is inconsistent mixing of present and past in the reporting clause, which changes the time frame of the report. Practising several examples of future in reported speech helps to fix these patterns firmly in memory.

Final Answer:
The correct reported sentence is He said that he would go to Mumbai someday the following month.