The Braille system, used by visually impaired people for reading, was developed by:
ALouis Braille
BEdward Jenner
CGalileo Galilei
DHelen Keller
Answer & Solution
Correct answer: A. Louis Braille
Louis Braille, himself visually impaired from a young age, developed the dot-based Braille system and published it in 1821. Letters and characters are formed by raised dots arranged in a 2 × 3 grid, read by touch.
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