This question seems to be incomplete. However, there is enough information to find the right answer.
Answer:
Matilda walked to the public library all by herself. This surprised Mrs. Phelps because Matilda being only four years and three months old is too young to be alone in public.
Explanation:
The question refers to Matilda, by Roald Dahl.
Matilda, a passionate reader since a very early age, was from a family that didn´t share nor understand her special abilities. Her father had refused to buy her a book, so she decided to go to the library. Since she was usually left alone in the afternoons, she just left her home and went to the library unsupervised, which is odd for such a young kid.
