which type of sentence is this? in beijing, china, eight luxury residential towers that were designed by…

which type of sentence is this? in beijing, china, eight luxury residential towers that were designed by steven holl architects are connected on the twelfth through eighteenth floors by enclosed glass and steel bridges. simple compound complex compound - complex
Answer
Brief Explanations:
A simple sentence has one independent clause. The given sentence "In Beijing, China, eight luxury residential towers that were designed by Steven Holl Architects are connected on the twelfth through eighteenth floors by enclosed glass and steel bridges." has one subject - "eight luxury residential towers" and one predicate - "are connected on the twelfth through eighteenth floors by enclosed glass and steel bridges". The "that were designed by Steven Holl Architects" is a relative - clause modifying the subject, but it doesn't make the sentence non - simple.
Answer:
simple