In the following English grammar question, a sentence is given in direct speech. Out of the four alternatives, select the option that best expresses the same idea in indirect or reported speech: The artist said, "I was painting a picture here at the bank of this river."

Introduction / Context:
Reported speech questions test your understanding of how to retell what someone said without using quotation marks. In direct speech, the exact original words of the speaker are kept inside inverted commas with a reporting clause outside the quotation. In indirect speech, we report the meaning in our own words, adjusting tense, pronouns, and time or place expressions so that the sentence is grammatically correct and logically consistent. This item asks you to select the correct indirect version of a past continuous statement that also contains words of place and reference to a specific river bank.

Given Data / Assumptions:

• The reporting verb "said" is in the past tense.
• The quoted clause begins with the first person pronoun "I".
• The quoted clause uses the past continuous form "was painting".
• The clause includes place and reference words: "here" and "this river".
• The converted sentence must keep the same meaning but follow standard rules of reported speech.

Concept / Approach:
When the reporting verb is in the past, normal backshift rules apply in English grammar. A past continuous form such as "was painting" usually becomes past perfect continuous, "had been painting", in reported speech. Deictic expressions related to place and reference are also adjusted from the viewpoint of the reporter: "here" is normally changed to "there" and "this" to "that". The first person pronoun "I" changes to "he" or "she" according to the speaker, and we usually insert the conjunction "that" after the reporting verb. All of this is done without changing the basic sense that the artist had been painting at that location earlier.

Step-by-Step Solution:
First, remove the comma and the quotation marks and join the two parts with the conjunction "that". Second, change the first person pronoun "I" in the quoted clause to "he", because the speaker is the artist. Third, backshift the tense from past continuous "was painting" to past perfect continuous "had been painting" because the reporting verb "said" is in the past. Fourth, replace the place word "here" with "there" and the reference "this river" with "that river" to reflect the different point of view in reported speech. Fifth, keep the rest of the vocabulary and the order of ideas unchanged so that the sentence still states that the artist had been painting a picture at the same river bank in the past.

Verification / Alternative check:
To verify the final sentence, read it as if you are explaining to a third person what the artist said earlier. The structure "The artist said that he had been painting a picture there at the bank of that river" clearly shows that the painting activity took place before the act of reporting. Pronouns, place words, and the reference to the river now make sense from the reporter's position, and the sentence sounds natural and complete. This confirms that the tense and deictic changes have been applied correctly.

Why Other Options Are Wrong:
Option A keeps "here" with "that river", which mixes two different viewpoints and is not idiomatic in reported speech. Option B uses "there" but keeps "this river", which again sounds as if the speaker and the reporter are standing in different places at the same time. Option D fails to backshift the tense and keeps "was painting" as well as "here" and "this river", so it is essentially still direct speech without quotation marks. Only option C correctly changes the tense, pronoun, and both place expressions while preserving the original meaning.

Common Pitfalls:
A common mistake in such items is to focus only on the verb tense and ignore words like "here" and "this". Another frequent error is to leave the first person pronoun "I" unchanged, even though in reported speech the speaker is usually referred to in the third person. Learners may also choose an option that sounds familiar but does not fully backshift the tense or that only changes some of the deictic words. To avoid these pitfalls, always check pronouns, tense, and time or place expressions together whenever you convert direct speech to indirect speech.

Final Answer:
The option that correctly converts the given direct sentence into reported speech is: The artist said that he had been painting a picture there at the bank of that river.