Error spotting in an English grammar sentence: The jug is made out of china clay. Choose which part of the sentence contains the grammatical or usage error, or state that there is no error.

Introduction / Context:
This question focuses on the correct preposition and phrase used with the verb made when describing the material of an object. The sentence talks about a jug and the substance from which it is formed. Such questions teach learners to distinguish between similar patterns like made of, made from, and made out of, and to recognise which is most natural in standard written English.

Given Data / Assumptions:
- Sentence: The jug is made out of china clay.
- Part (a): The jug
- Part (b): is made
- Part (c): out of china clay
- Part (d): No error
We assume that the exam expects the standard material expression used in formal grammar books.

Concept / Approach:
English distinguishes between made of, made from, and made out of. In many everyday situations, made out of is informal but acceptable. However, when we describe the basic material of an object whose form clearly shows the material, the preferred expression is made of. For example, the ring is made of gold, the table is made of wood. A jug whose material is china clay is best described as made of china clay. Therefore, out of in part (c) is considered incorrect in a formal error spotting question.

Step-by-Step Solution:
Step 1: Examine part (a) The jug. This is a simple subject noun phrase and is correct. Step 2: Examine part (b) is made. The passive form is appropriate because the focus is on the result, not on the maker, so this part is also correct. Step 3: Examine part (c) out of china clay. Here, out of is used with the material name china clay. Step 4: Recall the standard rule: when the original material can still be recognised in the final product, use made of plus the material, such as made of metal or made of glass. Step 5: Therefore, the correct phrase should be of china clay, not out of china clay. Step 6: Since parts (a) and (b) are correct and only part (c) requires change, the error is located in part (c) only.

Verification / Alternative check:
We rewrite the sentence in corrected form: The jug is made of china clay. This version is idiomatic and matches typical textbook examples. Another check is to substitute a different material: The cup is made of porcelain, not made out of porcelain in careful writing. These comparisons confirm that out of in the original sentence is stylistically wrong for an exam context, and it should be replaced with of.

Why Other Options Are Wrong:
- Error in part (a) only: The subject phrase The jug is fine, so this is incorrect.
- Error in part (b) only: The passive is made is the correct form and tense here, so there is no reason to change it.
- No error in the sentence: There is in fact a prepositional error in part (c), so this option is not acceptable.
- Error in more than one part: Only one segment needs correction, therefore this option is wrong.

Common Pitfalls:
Learners often overuse made out of because they hear it in casual conversation. They may also believe that made out of and made of are always interchangeable, which is not true in formal contexts. When facing such questions in an exam, it is safer to use made of for the basic material that remains visible in the finished object, and to reserve made from or made out of for special cases where the original material changes form or where very informal style is acceptable.

Final Answer:
Correct option: Error in part (c) only.