Philip Johnson was a modernist architect who sought clean lines, used steel and glass construction, and valued function in his design. Inspired by the Farnsworth House designed by Mies van der Rohe, Johnson designed his own house in Connecticut as made almost entirely of glass. The rectangular abode is now a tourist site, along with Johnson's entire property, including other buildings and his massive art collection.

Gehry, a modernist architect well known for flowing lines and unusual shapes, has built concert halls, museums, and government buildings around the world. Among his most notable works is the Guggenheim Museum in Bilbao, Spain, constructed out of titanium and glass, in shapes that are meant to evoke the countryside of Bilbao's Basque region.

La Sagrada Familia was planned as a massive church in Barcelona that would rival its Cathedral in size. After breaking ground in 1882, the church is still not totally finished. Importantly, its architect Antoni Gaudí was killed in a 1926 tram accident, and the work had to continue on under architects with different design aesthetics than its singular original designer.

Fallingwater is generally considered Frank Lloyd Wright's masterpiece, as the residence was constructed above and incorporated a waterfall. The residence, built in 1939, blended the interior and exterior of the building into Wright's perfect distillation of his "organic" philosophy of architecture. The property remained a residence for many years, but became a protected site in the mid-1960s.

John Augustus Roebling, a German immigrant, was the leading designer of bridges throughout the mid-nineteenth century in America. His masterpiece, however, was the Brooklyn Bridge, which was the first steel-wire suspension bridge ever built. Unfortunately, Roebling died in 1870, just as it was beginning construction, and his son Washington Roebling had to take over construction.

The Chrysler Building is most associated with Art Deco style. Minimalism is, like it sounds, associated with a simplicity that isn't often found in Early Modern works of architecture, particularly those that promoted power or faith. Thus, Versailles and the Cathedral aren't the right answer. Gaudi's Sagrada Familia is also famously elaborate. That leaves Lin's memorial, which is the best answer. 

Mannerism, Baroque, and Rococo are not from the twentieth century. Art Nouveau, the predecessor of Art Deco, is characterized by natural forms and structures with curved lines. There is often a nature motif in Art Nouveau works. Art Deco is known for its rich colors, bold geometry, and ornamentation.

Though many of these architects are known for either their prairie or organic styles, Wright designed the Guggenheim.

The Chrysler Building in New York City is a well-known example of the Art Deco artistic and architectural style. Art Deco is known for its bold, geometrical shapes, rather than the organic, flowing style of Art Nouveau, or the Greek-and-Roman-derivation of Neoclassicism. Art Deco was not intricate or natural. It embraced technology and the modern world, and reflected the glamour and luxury that modern technology provided. 

The Chrysler building is a good example of Art Deco architecture, as its spire is composed of symmetrical, bold, powerful geometrical shapes. It also makes sense that Art Deco, which represented glamour and luxury, would be used in that time period to build a skyscraper in New York, which in and of itself is a representation of the modern world.

Rococo and Gothic architecture are not from the 20th century.

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Frank Lloyd Wright built Fallingwater outside of Pittsburgh in 1935 for the owner of a Pittsburgh department store, Edgar Kauffman. Kauffman desired a specific, small plot of land to be used and wanted very specific elements. In order to build a large house in a tight space, Wright used a revolutionary cantilevered approach in his design, also incorporating natural elements like a waterfall, giving the building its name.