Meaning of 'turn up the sitting room clock'

[Jonas Ferreira]

English Language Proficiency Tests, Advanced Level

ESL/EFL Test #74 "At the End of the Day (3)", question 7

you could be subtle and ......... up the sitting room clock

(a) wind
(b) stir
(c) turn
(d) take

English Language Proficiency Tests, Advanced Level

ESL/EFL Test #74 "At the End of the Day (3)", answer 7

you could be subtle and wind up the sitting room clock

Correct answer: (a) wind

Your answer was: incorrect
you could be subtle and turn up the sitting room clock
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What does the whole sentence mean?

Jonas Ferreira

[Mister Micawber]

.
By overtly winding up the clock, you can draw your visitors' attention to the lateness of the hour, and subtly encourage them to leave.

Often also, a clock is wound at the end of a person's day, so the visitors may realize that it is the end of the host's day, and they should go home.
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Canadian-American native speaker
who teaches English for a living at Mister Micawber's
ESL cafe: Interview with Mister Micawber