Vasco de Game was the FIRST to reach india by sea, so he was indeed an explorer.
Henry the Navigator (no offense to him) was a joke. His title if fooling everyone, as he himself never even sailed once, he always sent others to do it for him (as he was a prince) This is your answer.
Bartholomeu Dias sailed around the southernmost tip of africa in 1488, so he was an explorer too.
Your answer is Henry