Which personal pronoun correctly completes the sentence? what is its use?

because so many leaves had fallen, their parents rake the yard.

a.
them; direct object

b.
them; indirect object

c.
they; direct object

d.
they; indirect object

After doing research, write an outline for a paper about an american author of your choice. remember to organize your outline according to the degree of importance that each idea holds. from that outline, write an essay of at least 500 words. remember to check your essay for errors. include your outline above the actual essay. replace the heading with your own original title. credit your sources using a manual of style such as: the american psychological association, the chicago manual of style, or the modern language association. ask your teacher which format is preferable. the difference in these styles is in the order the material is presented in each entry and the punctuation required. most papers in high schools use the modern language association.