Blue Options How Can I Display Default Option In Blue Color In A Value Prompt?

How can i display default option in blue color in a value prompt? - blue options

Hello, I try, a drop-down list, select HTML Web page, I would like to create

1) Ask the user a default. (For example, if there are three options for the AA, BB, CC, and at the beginning of the AA value should be automatically selected and should be the color blue, as if the ants, the color blue)
2) the selected item is displayed in blue

Can someone help me please ....