The correct answer is A. Lucy is a smart girl.
A smart person is someone who is intelligent and has a good understanding of things. They are able to learn new things quickly and easily, and they are able to solve problems effectively. Smart people are also often creative and imaginative.
B. Indecent means not decent or proper. It can also mean offensive or vulgar.
C. Active means full of energy and movement. It can also mean busy or occupied.
D. Scruffy means dirty or untidy. It can also mean unkempt or uncared for.
In this case, the word “smart” is used in a positive way to describe Lucy. It means that she is intelligent and has a good understanding of things. She is able to learn new things quickly and easily, and she is able to solve problems effectively. Lucy is also a creative and imaginative person.