Error spotting (lexical choice: hung vs. hanged): Identify the erroneous part (A/B/C) — choose D if there is no error — 'After the humiliating exposure / he hanged his head / in shame. / No error.' Clarify the distinct past forms of 'hang' in idioms versus judicial contexts.

Concept/Approach: Distinguish 'hung' vs. 'hanged'
Use hanged only for execution ('The prisoner was hanged'). For general meanings and idioms (pictures, heads, coats), the correct past form is hung.

Step-by-step correction
B: 'he hanged his head' → 'he hung his head'.Corrected sentence: 'After the humiliating exposure, he hung his head in shame.'

Common pitfalls
Overapplying 'hanged' to non-judicial contexts.

Final Answer
B — Use 'hung' in the idiom 'hung his head'.