Acell containing both sets of homologous chromosomes

Ineed to know why d is the correct answer asap

Which would best keep the oxygen cycle stable? a. cutting down jungles to create farmland b. eliminating parks in large cities c. dumping toxic chemicals into the ocean d. reducing the amount of deforestation d. reducing the amount of deforestation

How will you manage your time to accomplish the necessary tasks both on the job and at home?