Geometry

Question Analysis  
This question tests similarity of triangular pyramids by checking base side and height ratios.
The main focus is identifying uniform scaling across all dimensions.  

Key Concept Explanation  
Similar pyramids require base sides and height to scale by the same factor.
For triangular bases, all three sides must be proportional.  

Step-by-Step Solution  
Option A: Pyramid X  
Base sides: 8 cm, 10 cm, 12 cm  
Scale factor for base sides:  
, , (all equal to 2).  
Height: 16 cm  
Scale factor for height: .  
Conclusion: Base and height scale factors match (2). Similar to Pyramid R.  
Option B: Pyramid Y  
Base sides: 2 cm, 2.5 cm, 3 cm  
Scale factor for base sides:  
, ,

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