what would you do with a spare tire?

[Hellz]

so awhile ago i purchased 5 - 37x12.5 BFG M/T KM2 tires.

i bought 4 rims, and had 4 tires mounted.
since then, the 5th tire has been sitting in my garage.. brand new...
i have put maybe about 10k miles on my H2 with the tires on them.. while there is some wear on them, its not too back.. maybe about 1/4 is the difference from the new to used...

would you

A: get a new rim and mount the tire just to have a spare
B: get a new rim and mount tire and put on the vehicle and get it in the rotation
C: hold on to the tire unless its time to get new tires and either but 3 of the same, or a new set and sell the spare off?


personally, i am thinking of just getting a new rim and adding it to the rotation. i just dont know if the wear on the other tires is so much that it isnt going to really help by adding a new tire.