Using context clues, what does "native advertising" mean in this sentence? "In the battle to scape a new business model from the wreckage wrought by the internet, legacy media owners have gone the same way, offering native advertising and branded content to clients who want it to look as close as possible to editorial."

a. advertising that is seamlessly integrated into content
b. advertising that is specific to indigenous people
c. advertising that is designed for a certain location