Step 1: Understanding the problem.
We need to divide a cube into 8 smaller cubes, each of equal size and shape. A cube has 6 faces, 12 edges, and 8 vertices. We are to perform straight cuts that go from one end of the cube to the other, ensuring that each cut divides the cube into equal pieces.
Step 2: Dividing the cube using 3 cuts.
To divide the cube into 8 smaller cubes, consider the following approach:
- The first cut should divide the cube in half, cutting through the center along one axis. This gives 2 equal pieces.
- The second cut should divide each of the two pieces in half along a different axis. This results in 4 pieces.
- The third cut should divide each of the 4 pieces in half along the third axis, resulting in 8 smaller cubes.
Thus, 3 straight cuts are sufficient to divide the cube into 8 smaller cubes, each of equal size and shape.
Step 3: Conclusion.
The minimum number of cuts required to divide a cube into 8 equal pieces is 3. Therefore, the correct answer is \( \boxed{3} \).