Which is a compound-complex sentence? while they were walking on campus, dwayne admired the buildings, and michelle imagined attending classes in this beautiful place. daily exercise is beneficial to your health, therefore you must take several precautions to avoid injuries. our experienced tour guide, who grew up in the area, directed us toward some amazing local scenes. the electronic merchandise was defective, as it had been severely damaged during shipment.

A compound-complex sentence consists of at least two independent sentences, and at least one subordinate sentence. Having this in mind, the correct answer is the first option - While they were walking on campus, Dwayne admired the buildings, and Michelle imagined attending classes in this beautiful place.
There is one subordinate sentence here (while they were walking on campus) and two independent ones (the rest of the sentence). The other options have only one independent clause, or they don't have a subordinate clause at all.

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