Leonardo da Vinci, an Italian polymath, was a painter, draftsman, engineer, scientist, theorist, sculptor, and architect. He is widely considered one of the greatest painters of all time. Born in 1452, he is famous for iconic works like 'Mona Lisa' and 'The Last Supper'. The 'Mona Lisa', his most famous portrait, is believed to have been started around 1503.
Around what year did Leonardo da Vinci start painting the 'Mona Lisa'?
A) 1452
B) 1503
C) 1492
D) 1519