Based on the answers provided, the following corrections need to be made to the 3D object:

1. Modify the overall shape of the object to resemble a "U" shape. Currently, it appears more like a three-dimensional "K" shape. 

2. Ensure that the base of the object is clearly rectangular. The current images do not provide a clear view of the base, making it difficult to confirm its shape.

3. No changes are required in terms of the object being extruded in one dimension as this aspect is already correct.

4. Provide clear indications or features that can help determine the size of the extrusion. Currently, it is unclear whether the extrusion is small or large due to lack of context or scale.