Which of the following is a sentence fragment? The first tiny purple crocuses bloomed in February. High up in the willow trees in the springtime. Covered in snow, the branches reflected the sunlight.

Sentence fragments are groups of words that appears like sentences, but aren't. To be a sentence, clusters of words essential to have as a minimum of one independent clause. An independent clause is several group of words that cover both a subject and a verb and can be independent. So for this, the answer is the "High up in the willow trees in Springtime." Since it doesn’t have a verb or subject.