What's the main ingredient of Serum?

Vitamin C Serum Ingredients: 20%

Sodium Hyaluronate, Hamamelis Virginiana (Witch Hazel) Extract, AloeLeaf Extract, Rosa Canina Fruit Extract, Chamomilla Recutita (Matricaria) LeafExtract 

HA Serum Ingredients: 5%

Hamamelis Virginiana(Witch Hazel) Extract, Aloe Leaf Extract, Vitamin C, Hydrolyzed wheat protein,Geranium Essential Oil

Retinol Serum Ingredients: 2.5%

Sodium Hyaluronate, Tocopherol (Vitamin E), Licorice Root Extract,Retinol (Vitamin A), Scutellaria Baicalensis Root Extract, Green Tea Extract