To choose a storybook for our students, it is important to balance authenticity and readability. In this sense, readability refers to
_______.
(A) a measure of how easily individual letters or characters can be distinguished from each other
(B) the degree of lexical and structural difficulty in the text that may challenge students
(C) the extent to which students find the book interesting, enjoyable and appropriate for their goals in learning English
(D) an identifiable line of story development in children’s stories