To prepare dipping sauce, combine yogurt, sour cream, honey, and mustard in a small bowl.
Hold carrots against cutting board and trim off ends. Cut each half, crosswise, then lengthwise to make four pieces.
Arrange each plate by putting two carrot pieces side-by-side in the center. Arrange broccoli around the carrots, forming a cluster. Arrange the tomatoes at the top of the plate. Spoon dip around the base of carrots and sprinkle with parsley.