Which of the following was an unusual concept found in Spanish Mining Law? a. If the discoverer registered and worked the mine, ownership was granted. b. Any person except a friar or clerical was free to discover and work mines. c. To sell or will a mine to heirs, unanimous approval from the miners was needed. d. If someone dug a hole to a mine, it belonged to Spain. Please select the best answer from the choices provided A B C D