All four can threaten biodiversity. (1) Global warming changes species distribution and threatens ecosystems. (2) Habitat fragmentation isolates populations, reducing genetic diversity and increasing extinction risk. (3) Alien invasive species outcompete and displace native species. (4) Promotion of vegetarianism and shift to commercial farming practices — while seemingly benign, commercial monoculture farming (associated with vegetarianism's demand for grains/vegetables) replaces diverse natural habitats, reduces crop variety and displaces local traditional farming — this threatens agricultural biodiversity. Hence all four are threats.