To solve this problem, follow these steps:

1. Calculate the circumference of the circle:
The circumference $C$ of a circle is given by:
$$C=2\pi r$$
where $r$ is the radius of the circle. Given $r=28$ cm and $\pi =\frac{22}{7}$, we can calculate:
$$C=2\times \frac{22}{7}\times 28$$
$$C=\frac{44\times 28}{7}$$
$$C=\frac{1232}{7}=176\text{ cm}$$

2. Find the length of the wire used for the square:
When the wire is re-bent into a square, the length of the wire will be the perimeter of the square. Therefore, the perimeter of the square is also 176 cm.

3. Calculate the side length of the square:
The perimeter $P$ of a square is given by:
$$P=4\times \text{side length}$$
Let $s$ be the side length of the square. We can solve for $s$:
$$4s=176$$
$$s=\frac{176}{4}=44\text{ cm}$$


The length of the side of the square is 44 cm.

The correct answer is A. 44 cm.