Which of the following are examples of evolution by anthropogenic action?
(a) Evolution of DDT-resistant mosquitoes
(b) Adaptive radiation of marsupial mammals
(c) Evolution of antibiotic-resistant bacteria
(d) Convergent evolution of potato and sweet potato

Excess use of herbicides, pesticides, etc., has only resulted in selection of resistant varieties in a much lesser time scale. This is also true for microbes against which we employ antibiotics or drugs against eukaryotic organisms/cell. Hence, resistant organisms/cells are appearing in a time scale of months or years and not centuries. These are examples of evolution by anthropogenic action.