Final answer:
The Spanish 100 Peseta banknote issued in 1970 features the image of Antoni Gaudí, a master of Catalan Modernism, known for his influential architectural works such as the Sagrada Familia.
Step-by-step explanation:
The Spanish 100 Peseta banknote issued in 1970 features the image of Antoni Gaudí, a renowned Spanish architect known for his distinctive style termed Catalan Modernism.
Gaudí's works, including the famous Sagrada Familia in Barcelona, Spain, demonstrate his unique approach that incorporated organic elements, curved surfaces, and colorful materials.
While Pablo Picasso was also an influential Spanish artist, his contributions pertain more to the art world with the creation of Cubism and works like 'Guernica', which are separate from the design of the 100 Peseta banknote.