The correct sentence is option a) "Here is our check, Mr. Vons, for $7.35."
The sentence is punctuated correctly because it includes both commas appropriately. Commas are used to set off the name "Mr. Vons" as an appositive, providing additional information about the recipient of the check. Additionally, there is another comma used to separate the introductory phrase "Here is our check" from the rest of the sentence. This proper use of commas makes the sentence clear and grammatically correct.
I hope this helped!
~~~Harsha~~~