1 That very singular man, old Dr. Heidegger, once invited four venerable friends to meet him in his study. There were three white-bearded gentlemen, Mr. Medbourne, Colonel Killigrew, and Mr. Gascoigne

1 That very singular man, old Dr. Heidegger, once invited four venerable friends to meet him in his study. There were three white-bearded gentlemen, Mr. Medbourne, Colonel Killigrew, and Mr. Gascoigne, and a withered gentlewoman, whose name was the Widow Wycherly. They were all melancholy old creatures, who had been unfortunate in life, and whose greatest misfortune it was that they were not long ago in their graves. It is a circumstance worth mentioning that each of these three old gentlemen, Mr. Medbourne, Colonel Killigrew, and Mr. Gascoigne, were early lovers of the Widow Wycherly, and had once been on the point of cutting each other's throats for her sake. And, before proceeding further, I will merely hint that Dr. Heidegger and all his foul guests were sometimes thought to be a little beside themselves,--as is not unfrequently the case with old people, when worried either by present troubles or woeful recollections. Which dictionary definition of singular BEST fits the context of the first sentence of the short story? A) unmarried B) remarkable, extraordinary C) only being one, not plural D) pertaining to something individual