ByteOrdering is an option for BinaryRead, BinaryWrite, and related functions that specifies what ordering of bytes should be assumed for your computer system.
CellBaseline is an option for Cell which specifies where the baseline of the cell should be assumed to be when it appears inside another cell.
CellEvaluationFunction is an option to Cell which gives a function to be applied to every expression from the cell that is sent to the kernel for ordinary evaluation.
ChartBaseStyle is an option for charting functions that specifies the base style for all chart elements.
CheckAbort[expr, failexpr] evaluates expr, returning failexpr if an abort occurs.
C
(Built-in Mathematica Symbol) C[i] is the default form for the i\[Null]\[Null]^th parameter or constant generated in representing the results of various symbolic computations.
ColorFunctionScaling is an option for graphics functions that specifies whether arguments supplied to a color function should be scaled to lie between 0 and 1.
ColumnLines is an option for the low-level function GridBox which specifies whether lines should be drawn between adjacent columns.
ColumnsEqual is an option for the low-level function GridBox which specifies whether all columns in the grid should be assigned equal width.
ColumnSpacings is an option for the low-level function GridBox which specifies the spaces in ems that should be inserted between adjacent columns.