Which famous myth about carrots started as WWII British propaganda?

The science is pretty sound that carrots, by virtue of their heavy dose of Vitamin A (in the form of beta carotene), are good for your eye health. But the truth has been stretched into a pervasive myth that carrots hold a super-vegetable power: that carrots improve night vision. But carrots cannot help you see better in the dark any more than eating blueberries will turn you blue. Researchers believe that the myth was reinforced and popularized by the British Ministry of Information during WWII, an offshoot of a subterfuge campaign to hide a technology critical to an Allied victory, the development of a new, secret radar technology.

Source: Smithsonian Magazine