Which style rule is correct in an external style sheet?

Maria wants to use Cascading Style Sheets (CSS) to apply formatting styles to her Web pages. In her style sheet, she sets the page’s background color to blue and the font to Arial. Which style rule is correct in an external style sheet?

A.
body (bgcolor: blue; font-type: arial).

B.
style=body (background: blue; font: arial).

C.
body (background: blue; font-family: arial).

D.
<style= body (bgcolor: blue; font-family: arial)>.