CLEAN: Hong Kong scans travellers from Japan for radiation

The video begins with a simple exchange of words, 'Knock, knock' followed by 'Yep', indicating a basic interaction or greeting scenario.

What is the significance of the phrase 'Knock, knock' in this context?

• It indicates a joke.

• It shows urgency.

• It is a greeting.

• It is a farewell.

How might the tone of the conversation change if the second character had responded differently?

• It would be more serious.

• It would be more humorous.

• It would be more confusing.

• It would remain the same.