Sentence:  There are three <WSD>possibilities</WSD> : ( a ) **f remains tangent to C as it is translated ; ( b ) **f moves away from C and does not intersect it at all for **f ; ( c ) **f cuts across C and there are two ordinary intersections for every t in **f . 
Meaning of the word marked with <WSD> tags:  capability of existing or happening or being true