Final answer:
The sentence is a compound-complex sentence because it includes two main clauses and one subordinate clause initiated by 'Because'.
Step-by-step explanation:
The sentence in question is: 'Because the high winds are blowing, the fire may spread rapidly, and we have been ordered to evacuate.' This sentence is classified as a compound-complex sentence. It contains two main clauses which are 'the fire may spread rapidly' and 'we have been ordered to evacuate', and a subordinate clause beginning with 'Because' as in 'Because the high winds are blowing'. The main clauses can stand alone as sentences, while the subordinate clause cannot. This sentence structure allows the writer to express multiple ideas in a single, cohesive statement.