The choice of DDT as the correct answer is based on its history of use, which started in the mid-20th century. Specifically, DDT (dichloro-diphenyl-trichloroethane) was first synthesized in 1874, but it wasn't until World War II, during the 1940s, that it gained widespread application as an insecticide. Its use in agriculture became prominent only after this period, making it a relatively modern pesticide in comparison to the others listed.
In contrast, the Bordeaux mixture, composed of copper sulfate and lime, was formulated in the 1880s and is one of the oldest fungicides used for grapevine diseases. Nicotine has a long history of use as a natural pesticide, dating back to at least the 17th century when it was used by early farmers. Sulfur has been used as a pesticide for thousands of years, recognized for its effectiveness against various pests and diseases, particularly in horticulture.
Thus, DDT stands out as the choice that did not fit into the group of early pesticides used before 1900, as its emergence as a common pesticide occurred long after that period.