English grammar error-spotting (idiom ‘‘have a hand in’’ + article usage): Identify the erroneous segment among A–D; choose ‘‘No error’’ only if the sentence is entirely correct: ‘‘Though he stoutly persisted in denying his involvement in the case, / the facts made it very clear / that he had hand in the cruel murder of his wife. / No error.’

Given data

• C contains the idiom ‘‘had hand in’’ without an article.

Concept / ApproachStandard idiom: ‘‘have a hand in (something)’’ meaning ‘‘be involved in’’. The article ‘‘a’’ is mandatory; without it, the phrase is ungrammatical in formal English.

Correction‘‘… the facts made it very clear that he had a hand in the cruel murder of his wife.’’

Common pitfalls

• Dropping the article in fixed expressions (e.g., ‘‘in a hurry’’, ‘‘have a look’’, ‘‘have a hand in’’).

Final Answerthat he had hand in the cruel murder of his wife.