Addressing known errors: 
1. The amount water that the plants first received every day for the first 5 days might have been different.
2. The amount of sunlight each plant received throughout the entire experiment might have been different.
3. The amount of vinegar that plants in containers A and C might have been different.
4. The heights of the plants taken might not be accurate.
5. The sizes of the four containers were different.
6. The experiment was only carried out on one type of plant.