Carefully read the following sentences. 1. Ladybugs' markings are attractive to humans they are unattractive to predators. 2. Ladybugs' markings are attractive to humans but unattractive to predators. Sentence 1 contains one or more errors. Which technique is used in sentence 2 to correct the grammatical problems in sentence 1? A. adding a conjunction and rearranging phrases B. inserting a semicolon C. adding an independent clause D. creating a subordinate clause