Correct Option: D

Bentham & Hooker wrote the book Genera Plantarum. Bentham began with the Flora Hongkongensis in 1861, which was the first comprehensive work on any part of the little-known flora of China and Hong Kong, including Hong Kong Croton. This was followed by the Flora Australiensis, in seven volumes (1863-1878), the first flora of any large continental area that had ever been finished. His greatest work was the Genera Plantarum, which begun in 1862, and concluded in 1883 in collaboration with Sir Joseph Dalton Hooker.