You Are Writing a Letter to a Potential Customer in Italy

You are writing a letter to a potential customer in Italy. Which of the following should you include in your letter?

A) clichés such as the buck stops here because the Italians appreciate North American sayings
B) abbreviations such as DBA to make your letter as concise as possible
C) weights and measures written using Italy's measurement standards
D) slang such as this is a really hot idea to sound more approachable