Transport of Ascorbic acid to the lens is done by –

I could not find any direct reference for this. I could find only following information. Ascorbic acid is not synthesized in the lens, but there is evidence that specialized transport mechanism exist to transport it into the lens. Ascorbic acid is transported into the lens by Na+ dependent specific transporter, i.e. specific vitamin C transporter (SVCT) SVCT1 & SVCT2. So, amongst the given options Na+ K+ ATPase seems to be best as ascorbic acid transport is Na+ dependent. But, I am not 100% sure.