Which of the following is punctuated correctly?
a) Greta whined "I want to go home" so we took her there instead of with us.

b) Greta whined, "I want to go home" so we took her there instead of with us.

c) Greta whined, "I want to go home," so we took her there instead of with us.

d) Greta said "I want to go home," so we took her there instead of with us.