Final answer:
The giant cockerel sculpture on the fourth plinth in Trafalgar Square is C. blue, designed by Katharina Fritsch as a symbolic artwork.
Step-by-step explanation:
The giant cockerel that was placed on the fourth plinth in Trafalgar Square in 2013 is C. blue. This sculpture is by artist Katharina Fritsch and is known for its vivid ultramarine blue color, standing in stark contrast against the historical backdrop of Trafalgar Square.
The cockerel, which is a traditional symbol of France, was chosen to provoke thoughts about national identity, military history, and cultural symbolism.