Correct option is A
Shorter side of an A4 sheet = 210 mm
Longer side of an A4 sheet = 297 mm
Shorter side of an A3 sheet = 297 mm
Longer side of an A3 sheet = 420 mm
The ratio of sheet = 1 : 2
Shorter side of an A4 sheet = 210 mm
Longer side of an A4 sheet = 297 mm
Shorter side of an A3 sheet = 297 mm
Longer side of an A3 sheet = 420 mm
The ratio of sheet = 1 : 2