Answer: The subordinating conjunction in the sentence provided is "where" and it demonstrates a relationship of place.
Step-by-step explanation: A subordinating conjunction is a word that introduces a dependent clause and connects this type of clause to an independent clause. The sentence "She can never remember where she left her glasses" is made up of an independent clause ("She can never remember") and a dependent clause ("where she left her glasses"). The subordinating conjunction linking both clauses is "where", which is also signaling a relationship of place.