The correct option is C Stub
The word for the phrase 'the short remaining end of a cigarette' is called Option B, 'Stub'. Option A, 'Stump' is the bottom part of a tree left from the ground after most of the trunk has fallen. Option C, 'Rag' is a torn piece of old cloth. Option D, 'Scrap' means not to continue with a plan. Thus, options A, C and D are incorrect options and the correct word for the given phrase is option B, 'Stub'.