In this error spotting question, the sentence is divided into parts labelled (A), (B), (C), and (D). Identify the part that contains an error: "Those sort of people (A) / are always nice (B) / to you on your face. (C) / No error (D)".

Introduction / Context:
This error spotting question focuses on agreement between demonstratives ("this", "that", "these", "those") and nouns like "sort" and "people". The sentence "Those sort of people are always nice to you on your face." sounds natural to some learners but is grammatically incorrect in standard English. You must identify which labelled part contains the error.

Given Data / Assumptions:

• Part A: "Those sort of people"
• Part B: "are always nice"
• Part C: "to you on your face."
• Part D: "No error"
• The sentence is describing a type of people who behave nicely in front of you, but not necessarily behind your back.

Concept / Approach:
When we use "sort of" or "kind of" with plural nouns, the correct demonstrative is "these" or "those" paired with a plural form of "sort" or "kind". There are two common correct patterns: "that sort of person" (singular) and "those sorts of people" (plural). In the given sentence, "those sort of people" mixes a plural demonstrative "those" with a singular noun "sort", creating a disagreement. Therefore, the error lies in Part A. It should be "that sort of person" (if speaking generally) or "those sorts of people" (if emphasising many kinds of such people).

Step-by-Step Solution:
Step 1: Look carefully at Part A: "Those sort of people". Step 2: Recognise that "those" is plural, while "sort" is singular. This is a mismatch. Step 3: Recall the correct patterns: "that sort of person" (singular) or "those sorts of people" (plural). Step 4: Check Part B: "are always nice". The verb "are" matches the plural noun "people", so this part is correct. Step 5: Check Part C: "to you on your face." This is a colloquial way of saying "to your face", but grammatically it is acceptable in the context of the exam. Step 6: Since only Part A breaks the correct pattern of demonstrative plus noun, it must be identified as the error.

Verification / Alternative check:
Rewrite the sentence correctly in two ways: "That sort of person is always nice to your face" (general singular) or "Those sorts of people are always nice to your face" (plural). Notice how we either keep both elements singular ("that" and "sort") or both plural ("those" and "sorts"). The exam sentence mixes "those" with "sort", which does not match either standard pattern, confirming that Part A is incorrect.

Why Other Options Are Wrong:
Part B uses the plural verb "are" correctly with the plural subject "people". Part C, though slightly informal, does not introduce a grammatical error. Part D "No error" is wrong because we have clearly found an error in Part A. There is no evidence of a second error that would justify the choice "More than one part has an error".

Common Pitfalls:
Learners often get used to hearing incorrect phrases like "those sort of things" in casual speech and assume they are acceptable in formal English. Exams, however, expect you to know the standard forms. To avoid such mistakes, pay attention to patterns like "this kind of book / these kinds of books" and "that type of machine / those types of machines" and practise them until they feel natural.

Final Answer:
The error is in Part A: Those sort of people, which should be corrected to a form like "those sorts of people".