Error Spotting – Choose the single segment (A–D) that contains a grammatical or spelling error; select ‘‘All correct’’ only if the entire sentence is correct. Sentence: A) He was polite B) but ferm in his C) dealings with the D) foreigners

Introduction / Context:
This question focuses on spelling accuracy in a common collocation of contrasting traits: “polite but firm.” Such pairings are frequent in professional communication and managerial writing, where firmness coexists with courtesy.

Given Data / Assumptions:

• The main clause describes a person who is both polite and firm.
• Segment B reads “but ferm in his,” which looks like a phonetic misspelling.
• No other segment exhibits a clear grammatical fault.

Concept / Approach:
Identify the core adjective that pairs with “polite.” The correct adjective is “firm,” not “ferm.” While accents may influence pronunciation, standard English spelling is fixed in formal exams. Additionally, the noun phrase “dealings with the foreigners” is grammatically acceptable in context.

Step-by-Step Solution:
1) Recognize the idiomatic pairing: “polite but firm.”2) Compare segment B’s spelling to the standard: “ferm” → “firm.”3) Ensure surrounding grammar is coherent: subject + linking verb + adjectives works well.4) Conclude that B contains the sole error.

Verification / Alternative check:
Substitute the correction: “He was polite but firm in his dealings with the foreigners.” The sentence now reads idiomatically and precisely.

Why Other Options Are Wrong:

• A: Correct simple past with copular verb “was”.
• C: Prepositional phrase is standard.
• D: Plural “foreigners” is appropriate given the generic context.

Common Pitfalls:
Letting pronunciation override spelling; misidentifying B as a style choice rather than a clear misspelling.

Final Answer:
but ferm in his