In this sentence improvement question, choose the correct adjective to replace "populous" in the sentence: "The new book written by Vikram Seth has become very populous."

Introduction / Context:
This sentence improvement question tests your ability to distinguish between similar-looking English words that have different meanings. The sentence given is "The new book written by Vikram Seth has become very populous." The idea is to say that the book is widely liked or enjoyed, but the word "populous" is typically used for places, not books. You must choose the correct adjective that fits naturally with "book" and expresses the intended meaning.

Given Data / Assumptions:

• Original sentence: The new book written by Vikram Seth has become very populous.
• Underlined word: populous.
• Options: populist, popular, populace, no improvement.
• The context indicates that the book has gained wide acceptance or admiration.

Concept / Approach:
"Populous" means having a large population and is usually used with countries, cities, states or regions. It is not used to describe books or other cultural products. "Popular" means liked or enjoyed by many people and is the correct adjective for books, movies, songs and so on. "Populist" is linked to a political style that claims to represent ordinary people, and "populace" is a noun meaning the general public. So "popular" is the only option that gives the right meaning and grammatical form.

Step-by-Step Solution:
Step 1: Identify the intended meaning: the book has become widely liked or successful among readers.Step 2: Recall that "popular" is the standard adjective used for such cases, as in "a popular novel" or "a popular song."Step 3: Examine "populous," which describes places crowded with people, such as "a populous city," and note that it does not fit with "book."Step 4: Examine "populist," which refers to a political leader or approach, and see that it has no connection with books gaining readers.Step 5: Examine "populace," which is a noun, not an adjective, meaning the ordinary people in a country.Step 6: Select "popular" as the correct option and reject "no improvement" because the original adjective is misused.

Verification / Alternative Check:
Replace the underlined word with each option. "The new book written by Vikram Seth has become very popular" sounds natural and matches common usage. "Has become very populous" would mean the book is full of people, which is nonsense. "Has become very populist" might apply to a politician or speech but not a book in this general context. "Has become very populace" is grammatically wrong because "populace" is not an adjective. This test clearly confirms that "popular" is the correct choice.

Why Other Options Are Wrong:
"Populous" collocates with geographical entities and cannot sensibly describe a book's reception. "Populist" is primarily political and refers to ideology, campaigns or leaders, not to general popularity of a work of art. "Populace" is a noun referring to people collectively and cannot function as an adjective modifying "book." "No improvement" would leave an incorrect and misleading word in place, so it must be rejected.

Common Pitfalls:
Students sometimes choose "populous" because they see the common root "popul" and assume all related words mean "well liked." To avoid this, it is useful to learn word families with examples: "popular book," "populous city," "populist leader," "the general populace." Connecting each word to a typical noun clarifies its correct usage. Recognising that exams frequently test such confusable pairs will encourage you to pay extra attention to context and collocation.

Final Answer:
The improved sentence is: "The new book written by Vikram Seth has become very popular."