$$40-8=32$$,  $$32\div4=8$$.  Mother used $$8$$ bottles. 
Mother baked $$40$$ cookies. She gave $$8$$ cookies to her friend and packed the rest equally into bottles. She put $$4$$ cookies in each bottle. How many bottles did she use? 
Options:
a: $$7$$ 
b: $$8$$ 
c: $$9$$ 
d: $$10$$ 