After incubation, you observe that your streak-plate has heavy, uniform growth but no isolated colonies. Which of the following could explain this result? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer. A streak plate achieves isolated colonies by physically diluting the culture as it is spread over the plate. After incubation, you observe that your streak-plate has heavy, uniform growth but no isolated colonies. Which of the following could explain this result? To be marked correct, you'll need to select all applicable statements, as there may be more than one correct answer.1. The specimen was a mixed culture.2. The plate is contaminated.3. Area three of the streak plate crossed into area one of the streak plate.4. The loop was not properly sterilized between plate sections.