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Which are correct? Thanks.
The population voiced its concerns/ their concerns by staging protests.
The crew refuse/ refuses to obey their coach/ its coach

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VladvThe population voiced its concerns/their concerns by staging protests.

Both are OK. Personally, I prefer 'their'.

VladvThe crew refuse/refuses to obey their coach/its coach.

British English: refuse; their
American English: refuses; their

CJ