Which of the following is a sentence fragment?

(1 point)
Responses

The first tiny purple crocuses bloomed in February.
The first tiny purple crocuses bloomed in February.

High up in the willow trees in the springtime.
High up in the willow trees in the springtime.

Covered in snow, the branches reflected the sunlight.
Covered in snow, the branches reflected the sunlight.

High up in the willow trees in the springtime.

The sentence fragment is: "High up in the willow trees in the springtime."