Eastern Newfoundland was explored by several European explorers, but it is primarily associated with John Cabot (option d) and his voyage in 1497. Cabot, an Italian explorer sailing under the English flag, is credited with being one of the first Europeans to reach North America after the Norse exploration. His landing in Newfoundland marked an important moment in the history of European exploration of the Americas. So, the correct answer is:
d. O Cabot