k-1 box 18 C non deductible expense-in the detail questions "c" wants info on the charity. the $901 is not a charitable contribution what do i do?

you can leave 18C blank in Turbotax. It doesn't use it. However, your tax basis is reduced by this amount which should be reflected in Part II section L. (if shown) 

by chance could you have something entered in 13C? It is for non-cash donations that require additional info,