4 ______ from Moscow!

Solution:

The sentence is an exclamation or greeting. We need a word that functions as a polite expression used when meeting someone or acknowledging their presence.

1. 'Greetings' is a formal way to say hello.
2. 'Regards' is a polite closing remark, usually in letters or emails.
3. 'Remarks' are spoken or written comments.

'Greetings' is the appropriate word to use as an exclamation when someone mentions they are from Moscow, implying a greeting or acknowledgement of their origin.

Answer: A Greetings