The correct answer is: None of the above.
The Periplus of the Erythraean Sea is an anonymous Greco-Roman navigational and geographical text, written in the first century CE, that describes the trade routes and ports of the Indian Ocean. The author is unknown, but is thought to have been a Greek merchant or sailor.
Ctesias was a Greek physician and historian who lived in the 5th century BCE. He is best known for his work Persica, which is a history of Persia from the time of Cyrus the Great to the reign of Artaxerxes II.
Pliny the Elder was a Roman naturalist who lived in the 1st century CE. He is best known for his work Naturalis Historia, which is a 37-volume encyclopedia of natural history.
Ptolemy was a Greek astronomer, geographer, and mathematician who lived in the 2nd century CE. He is best known for his work Geographia, which is a treatise on geography that includes a map of the world.
None of these authors is known to have written the Periplus of the Erythraean Sea.