"Quality" is a short story about an elderly boot maker whose name is Mr. Gessler. "whose" is the subordinating conjunction here, and creates the subordinating clause "whose name is Mr. Gessler."
The best answer could be: "Mr. Gessler is the name of an elderly boot maker, part of the short story "Quality".
Explanation:
The sentence presented is a compound one, and after rewriting it as a complex one, that becomes a subordinate clause by changing the order of the phrases and by adding some other words. Although a complex sentence may be an independent clause, this one becomes a subordinate clause because its phrases are reversed.
