How did the use of the song Follow the Drinkin' Gourd help enslaved people in the Underground Railroad?

A) Conductors would use it as a "road map" to find their way North at night.

B) Conductors would use it as a "warning" to tell other passengers it was not safe.

C) Conductors would use it as "code" to tell other passengers that they escape tonight.

D) Conductors would use it as a "password" to find safe passage to the North during the day​