What is the best way to indicate that text in a text input field is editable?

Imagine an app like yelp. In this case, you select the number of stars that you want to rate something. When you do, a pre-generated text is displayed in the text input field. You can either keep this text, as it is a useful pre-generated review, or you can delete this text and write your own.

I'm trying to decide what the best way is to indicate that this text is something that you don't HAVE to use, that it's an option, not forced upon you. That it is editable.

I can: - have an icon that indicates that it is editable (pencil?) (not very clear) - have text that says e.g. "tap to edit" (a bit messy, having a hint on screen) - have the text be "selected" the moment it appears on the screen. (cleanest way, but is it clear enough?)

Anything obvious I'm missing? What do you think is best?