During the past 100 years, the growth in human populations in the urban areas of industrialized nations has greatly contributed to all BUT one of these environmental problems

i think it's they require warm air

explanation:

tornados usually happen when it's raining right so when it's raining it cools down so if the temperature keeps changing then i think a tornado occurs sorry if it's wrong

the wires in the toaster turning red and the toast crisping and turning brown

idk why hjggjhjkhj

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).   so the answer is a.