A: "This thread is a spin-off of the other thread."
B: "This thread is a spin-off off the other thread."
C: "This thread is a spin-off off of the other thread."
Reasons?
EDIT: Added 2nd question
D: "This thread is a spin of the other thread."
E: "This thread is a spin off the other thread."
F: "This thread is a spin off of the other thread."
reasons?
B: "This thread is a spin-off off the other thread."
C: "This thread is a spin-off off of the other thread."
Reasons?
EDIT: Added 2nd question
D: "This thread is a spin of the other thread."
E: "This thread is a spin off the other thread."
F: "This thread is a spin off of the other thread."
reasons?