what is the best shampoo for natural red hair?
['Sulphate-Free. Nexxus Colour Assure Shampoo.', 'TRESemmé Colour Revitalise Shampoo. Buy Now.', 'For Coloured Hair. TIGI Bed Head Colour Goddess Oil Infused Shampoo.', 'Dove Colour Care Shampoo. Buy Now.', 'TIGI S Factor True Lasting Colour Shampoo.']