14 Sara ..... be from Mexico, but I'm not sure.

Analysis:

The sentence expresses uncertainty about Sara's origin. The modal verb 'may' is used to indicate possibility or uncertainty.

Breakdown:

• A can: Incorrect. 'Can' indicates ability or possibility, but 'may' is more appropriate for expressing uncertainty about a fact.
• B must: Incorrect. 'Must' indicates certainty or strong obligation.
• C may: Correct. 'May' expresses possibility or uncertainty.

Translated Question:

14 Сара ..... быть из Мексики, но я не уверен(а).