step overhangs unsupported structure will tip.

Step by step
Step 1: For each form, identify the footprint (contact area with the ground) and assess whether a person's weight on the top step falls within that footprint.
Step 2: Option A — legs splay outward from the base; the footprint is wide relative to the top step. Stable. ✓
Step 3: Option B — legs are vertical and directly under the top step but the geometry creates an unstable overhang condition when loaded at the top. ✗
Step 4: Option C — the frame leans or has an imbalanced structure that would tip when the top step is loaded. ✗
Step 5: Option D — legs splay outward in a stable scissor/X configuration; weight on top step stays within the footprint. ✓
Therefore the answer is A and D.

Why wrong options are wrong
Option B: The vertical-leg design means weight applied at the top-step edge pushes outside the narrow base footprint, causing tipping.
Option C: The angled structure shifts the centre of gravity outside the support base when loaded.

Remember for exam
Stability = centre of gravity falls within the base footprint. Outward-splayed legs create a larger effective base and resist tipping.

c:["3d-geometry","top-view","front-view","side-view","solid-geometry"] d:["A","C","D"] b:{"id":"uceed-2022-A223","slug":"uceed-2022-A223","exam":"UCEED","year":2022,"topic":"Spatial Reasoning","tags":"$c","type":"msq","difficulty":"hard","answer":"$d","title":"Shown below are 2 views of the same solid. Through which of the cutouts shown in the options, will the solid pass?","searchText":"Shown below are 2 views of the same solid. Through which of the cutouts shown in the options, will the solid pass? Spatial Reasoning 3d-geometry top-view front-view side-view solid-geometry","paper":"uceed-2022","question_number":23,"section":2,"part":"A"} e:["product-design","ergonomics","furniture","logical-deduction"] f:["A","D"] 11:["visual-pattern","shape-matchin

Shown below are different forms for a step-stool. Which of the forms will remain stable when a person is standing on the top step?