Which one of the following is the longest parallel of latitude ?

Which one of the following is the longest parallel of latitude ?

Tropic of Cancer
Tropic of Capricorn
Arctic Circle
Equator
This question was previously asked in
UPSC NDA-2 – 2021
The Earth is roughly spherical, and parallels of latitude are circles drawn parallel to the Equator. The circumference of these circles decreases as they move away from the Equator towards the poles. The Equator itself is the largest circle of latitude, dividing the Earth into the Northern and Southern Hemispheres.
The Equator is the 0-degree parallel of latitude and has the largest circumference among all parallels.
The Tropic of Cancer (23.5° N), Tropic of Capricorn (23.5° S), Arctic Circle (66.5° N), and Antarctic Circle (66.5° S) are all parallels of latitude, but their lengths are progressively shorter than the Equator.