Correct option is B
The
standard unit for luminous intensity is the
Candela (cd), which is one of the
seven SI base units. It measures the
brightness of a light source in a specific direction.
Definition of Candela (cd):
A
candela is defined as:
"The luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency
540 × 10¹² Hz (green light) and has a radiant intensity of
1/683 watt per steradian in that direction."
· A
standard wax candle emits approximately
1 candela.
· A
typical LED flashlight may have
100-500 candelas.
· A
car headlight emits around
20,000 candelas.
