Many of the technical ideas and innovations that led to the construction of the first skyscrapers were initially explored in Chicago by which of the following architects?

Walter Gropius was a significant figure in modern architecture, known for founding the Bauhaus School. However, his work primarily focused on industrial design and the integration of art and technology rather than the early skyscraper innovations specific to Chicago.

Although Frank Lloyd Wright contributed greatly to architecture and designed some innovative structures, he is primarily recognized for his philosophy of organic architecture and designs like the Prairie School. His focus was not on the skyscraper movement in Chicago, which Sullivan significantly influenced.

Le Corbusier was influential in modern architecture, particularly in promoting functionalism and urban design concepts in Europe. His ideas did not specifically address the early skyscraper movement in Chicago, where Sullivan's contributions were foundational.

I. M. Pei is known for his modernist designs and iconic buildings, such as the Louvre Pyramid. However, his work occurred later in the 20th century and did not contribute to the early skyscraper innovations that Sullivan pioneered in Chicago.