Final answer:
The sentence provided is neither a compound nor a complex sentence; it is a simple sentence with just one independent clause.
Step-by-step explanation:
The sentence "When it finally opened, she rushed inside with the other shoppers" is not a compound sentence or a complex sentence. It is a simple sentence with one independent clause and no dependent clauses.
A compound sentence contains at least two independent clauses connected by a coordinating conjunction (e.g., and, or, but), while a complex sentence contains one independent clause and at least one dependent clause introduced by a subordinating conjunction (e.g., because, since, when). The sentence in question does not fit the criteria for either structure.