The term 'PUMP OPTION' refers to the different types of fuel available at a gas station. The four solutions for this crossword are PREPAY (6 letters), REGULAR (7 letters), DIESEL (6 letters), and PREMIUM (7 letters). PREPAY is a type of fuel that requires payment before pumping, while REGULAR is the most common type of fuel. DIESEL is a type of fuel used in DIESEL engines, and PREMIUM is a higher-grade fuel that is more expensive than REGULAR fuel.