Which part of the personal letter is the opening greeting?

54 Blue Springs Rd
Ashland City, Tennessee

March 12, 2015
Dear Mrs. Hawthorne,
It gives me great pleasure to tell you that your short story "The Secret of the Lotus Garden" has been voted as the short story of the year by our readers. You'll soon receive a formal letter and a $300 cash prize. You will also receive a gift basket containing four items: a dictionary, a thesaurus, a metal pen, and a handmade notebook. The pen, which is an exclusive product of Klaus silver crafts, will be engraved with your name. However, we aren't sure which name you would like on the pen—your real name or the name under which your story was published. Please let me know so that I can send your gift basket soon.
Regards,
Jamie Redford