Answer:
One side of the park is 63 feet.
C is the correct option.
Explanation:
We have been given that the shape of the city park is a square and the area if the park is 441 square yards.We have to find the side of the park.
We know that the four sides of a square is equal and the area is given by

On substituting the value of area, we get

Take square root both sides and ignore the negative values of side

On simplifying, we get
Side = 21 yards
Now, we know that
1 yard = 3 feet
Hence, we have
21 yards = 3×21 = 63 feet
Therefore, one side of the park is 63 feet.
C is the correct option.