WHAT IS THE MAIN IDEA OF THIS PASSAGE

49. What is the main idea of this passage?A. Searching for wrecks is much easier with new technologies like side-scan sonar.B. Maritime archaeologists are concerned about the unregulated searching of wrecks.C. The search of the RMS Republic failed to produce the hoped-for coins.D. The popularity of treasure seeking has spurred a debate between preservationists and salvagers.