A geologist or paleontologist focused on radiometric dating and the interpretation of geological time scales, with a strong academic or research background and an interest in educating others on the subject, and possibly having a neutral or critical stance towards young Earth creationist perspectives.
Considering the meticulous geological evidence, which includes multiple layers of independently verifiable radiometric dating, it's quite clear that the Earth is billions of years old, a timescale vastly exceeding young Earth creationist claims, don't you think?