In this sentence improvement question, replace the bracketed idiom in 'By rescuing the child from fire, the local resident (added another feather to his cap.)' with the option that best conveys the intended meaning.

Introduction / Context:
This question checks your grasp of English idioms and your ability to interpret them correctly in context. The given sentence uses the expression 'added another feather to his cap' to describe the act of rescuing a child from a fire. In sentence improvement questions, you either replace the bracketed portion with a clearer equivalent or keep it as it is, depending on correctness and clarity. Here, the task is to pick the option that best paraphrases the idiom's meaning in simple English.

Given Data / Assumptions:
- Original sentence: 'By rescuing the child from fire, the local resident (added another feather to his cap.)'
- Options describe possible meanings: significant achievement, being gifted, being crowned, or no improvement.
- 'Feather in one's cap' is a standard idiom meaning an achievement or honour that one can be proud of.
- The context is an act of bravery that enhances the person's reputation.

Concept / Approach:
The idiom 'to add a feather to one's cap' means to gain a new distinction, achievement or credit that adds to one's public image or personal pride. It does not literally mean receiving a physical gift, crown or reward, although those might happen separately. When choosing the best improvement, you should look for the option that captures the idea of earning another notable success or highlight in one's record.

Step-by-Step Solution:
Step 1: Interpret the context: the local resident performed a brave, admirable act by rescuing a child from a fire. Step 2: Recall that 'added another feather to his cap' means he gained another achievement or honour to his name. Step 3: Option (a) 'made a significant achievement' directly states that he achieved something important. Step 4: Option (b) 'was gifted with precious thing' changes the meaning to receiving a valuable object, which is not implied in the idiom. Step 5: Option (c) 'was crowned and rewarded' overemphasises formal recognition and ceremony, which is not mentioned in the sentence. Step 6: Option (d) 'No improvement' would keep the idiom, but the question specifically asks for an improvement of the bracketed part into simpler meaning.

Verification / Alternative check:
Replace the bracketed idiom with each option in the sentence: 'By rescuing the child from fire, the local resident made a significant achievement.' This is a clear, natural and accurate restatement of the idea that his reputation and record of good deeds improved. The other options either introduce new information (a gift, a crown) or keep the idiom without clarification. Given that sentence improvement usually aims at clarity and correctness of meaning, option (a) is the most suitable choice.

Why Other Options Are Wrong:
Option (b) is wrong because nothing in the sentence suggests that someone gave him a precious object; the focus is on his action. Option (c) is wrong because many acts of bravery are not literally crowned, and the idiom does not require physical rewards. Option (d) is less appropriate because the test is specifically asking for an improved, clearer expression of the meaning rather than reusing the idiom itself.

Common Pitfalls:
Learners sometimes treat 'No improvement' as a safe default, but you must check whether the bracketed part truly needs change. Here the idiom is correct, yet the pattern of the question and the options shows that they want a plain-language equivalent. Another pitfall is focusing on prestige words like 'crowned' and 'precious', which make the sentence sound dramatic but distort the original sense. Always prioritise accuracy of meaning over dramatic flavour in such questions.

Final Answer:
The bracketed part is best improved as 'made a significant achievement'.