Can Anything Be Done to Stretch Out the Fuel Supply

Can anything be done to stretch out the fuel supply for fission nuclear reactors so that such reactors could be used for many more centuries?

A) No, because fission reactors must use uranium, and uranium resources will run out within a century.
B) No, because fission reactors must use plutonium, and plutonium resources will run out within a century.
C) Yes, by using uranium that is less highly enriched that the uranium fuel in use today.
D) Yes, by converting the ²³⁸U into ²³⁵U and then fissioning the ²³⁵U.
E) Yes, by converting ²³⁸U into plutonium and then fissioning the plutonium.