Step 1: Understanding the influence of size reduction equipment.
- Size reduction equipment affects particle size, shape, porosity, and surface texture.
- However, true density is an intrinsic property of a material and remains unchanged.
Step 2: Explanation of incorrect options.
- (A) Porosity: Affected by particle size and packing arrangement.
- (B) Shape: Different grinders and crushers produce different particle shapes.
- (C) Surface roughness: Influenced by the type of mill or cutting mechanism.
Step 3: Selecting the correct option.
Since true density remains constant regardless of size reduction equipment, the correct answer is (D) True density.
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