Example 8 A truck arrives at the edge of a 563-mile-wide desert. The truck consumes on average one gallon of gasoline per mile. The truck, in addition to its own fuel tank, has a spare fuel tank that can hold a maximum of 315 gallons of gasoline, and there is no other way to carry fuel (there is an ample supply of gasoline at the edge of the desert, and fuel depots can be set up along the way). Then, to cross the desert, the truck will consume at least $\qquad$ gallons of gasoline?
(1989, National Middle School Elite Selection Contest for the Tongda Scholarship)
(A) 4725
(B) 1575
(C) 563
(D) 1408
(E) The car cannot cross the desert at all.
Analysis: Operation method. To consume the least amount of gasoline, one should try to avoid retracing steps as much as possible. Therefore, with one full tank, 315 gallons of gasoline can cover a maximum of 315 miles; with two full tanks, a fuel storage point can be established 315 miles from the opposite side, allowing a maximum distance of $315 \div 3 + 315$ $= 420$ miles; with three full tanks, fuel storage points can be established 315 miles and 420 miles from the opposite side, allowing a maximum distance of 315 $\div 5 + 420 = 483$ miles; and so on, with five full tanks, the maximum distance is $315 \div 7 + 315 \div 9 + 483 = 563$ miles.
Therefore, the correct choice is (B).
Note: In fact, the most economical use of fuel and the farthest reachable distance is