In this idiom and phrase question, select the option that best expresses the meaning of the expression Thumb one's nose, used about a person's attitude or behaviour.

Introduction / Context:
This question asks about the meaning of the idiom Thumb one's nose, which describes a form of disrespectful behaviour. Idioms often come from old gestures or cultural practices and now function as figurative expressions in modern English. Understanding idioms is important for interpreting literature, news, and everyday conversation, where such expressions frequently appear to convey attitudes like respect, contempt, or amusement in a compact form.

Given Data / Assumptions:

• The idiom is: Thumb one's nose.
• The options describe various behaviours or personality traits: being ill mannered, showing affection, scolding someone, expressing scorn, and avoiding responsibility.
• The context of the idiom is usually negative, describing an attitude of mockery or disrespect.
• We assume standard modern English usage, where the idiom refers to a figurative gesture of contempt rather than a literal physical action.

Concept / Approach:
Historically, thumbing the nose at someone was an insulting gesture made by placing the thumb on the nose and wiggling the fingers. In modern figurative usage, to thumb one's nose at someone or something means to show defiance, disrespect, or scorn toward a person, rule, or authority. Therefore, the correct option must capture this sense of mockery or contempt, not positive feelings or neutral actions. We should look for the choice that directly mentions scorn or a similar negative emotional attitude.

Step-by-Step Solution:
Step 1: Recall that the idiom thumb one's nose means to show contempt or mock something, often by ignoring or defying it. Step 2: Examine option a, an ill-mannered person. This describes a type of person, not a specific act of expressing scorn. While someone who thumbs their nose may indeed be ill mannered, this option is not precise enough and does not capture the idiom's meaning directly. Step 3: Examine option b, to show affection. This clearly contradicts the negative tone of the idiom, as affection is positive and friendly. Step 4: Examine option c, to scold a naughty person. This describes a form of discipline or correction, not mockery or contempt. Step 5: Examine option d, to express scorn. This matches the meaning of showing contempt or disdain for something, which is exactly what the idiom conveys. Step 6: Examine option e, to avoid responsibility. Dodging responsibility is different from openly mocking or defying something, so it does not fit the idiom. Step 7: Therefore, option d, to express scorn, is the best and most accurate explanation of the idiom.

Verification / Alternative Check:
Consider a sentence such as The company thumbed its nose at environmental regulations, continuing to pollute despite repeated warnings. Here, thumbed its nose clearly means showed contempt for or defied the regulations. Another example is He thumbed his nose at tradition and refused to wear formal clothes to the ceremony, which again shows disdain or disrespect. In both cases, the idiom does not describe affection, scolding, or avoidance but a deliberate show of scorn. This confirms that expressing scorn is the correct interpretation.

Why Other Options Are Wrong:
Option a, an ill-mannered person, refers to a general type of person rather than the specific act or attitude expressed by the idiom.
Option b, to show affection, is opposite in sentiment to the contempt implied by the idiom.
Option c, to scold a naughty person, describes a verbal reprimand and does not match the mocking, defiant image of thumbing one's nose.
Option e, to avoid responsibility, involves evasion rather than open contempt or mockery.

Common Pitfalls:
A common pitfall is to choose a vaguely negative sounding option like an ill-mannered person simply because the idiom seems rude. However, idioms usually describe specific actions or attitudes, and the correct explanation should match that specificity. Another mistake is to guess based on partial knowledge of the literal gesture without understanding its figurative use in sentences. To improve performance on idiom questions, it is helpful to learn them in context with example sentences that show how they are used in real communication.

Final Answer:
The idiom Thumb one's nose means to express scorn, so option d is correct.