How do bulldozers and graders differ in their primary earthmoving roles?

• A. Bulldozers finish surfaces; graders push material.
• B. Bulldozers dig trenches; graders plant trees.
• C. Bulldozers push and move material with a blade; graders shape and finish surfaces to meet precise elevations and slopes.
• D. They have identical roles.

Answer: (C)

Bulldozers and graders serve different stages of earthmoving: bulldozers move large amounts of material quickly using a front blade, while graders shape and finish surfaces to exact elevations and slopes. The bulldozer pushes soil, rock, or debris to clear areas, rough-grade a site, or push material into piles. The grader, with its long adjustable blade, is used to fine-tune the surface, removing highs and filling lows to meet precise grade specifications and create smooth, drivable surfaces with the correct slope for drainage. In practice, bulldozers handle bulk moving and initial shaping, and graders handle precision finishing.