I was in my local grocery store last night and this made me do a double take

Do you read this as:
A 5 cents off per gallon.
B .05 cents of per gallon. As in 1/20th of 1 cent.
C Something else entirely.
I asked an employee about it (who was clearly not a teen but late 20s/early 30s). She told me, "Ohhhhh that actually means its 50 cents off per gallon."

Do you read this as:
A 5 cents off per gallon.
B .05 cents of per gallon. As in 1/20th of 1 cent.
C Something else entirely.
I asked an employee about it (who was clearly not a teen but late 20s/early 30s). She told me, "Ohhhhh that actually means its 50 cents off per gallon."