A <u>complex sentence</u> is formed by an independant clause and a subordinate clause. In the example provided, the independant clause is "my nose runs constantly" and the subordinate clause is "when I get a cold".
The rest of the options do not apply since a <u>simple sentence</u> is formed by just an independant clause. A <u>compound sentence</u> is formed by two independant clauses joined by a semicolon or coordinating conjunction.
A <u>compound-complex sentence</u> is formed by 2 independant clauses and a subordinate one.
Anne never really got to know Germany well, though, and would always struggle with the German language, because the family moved to Amsterdam when she was only four years old.