Why did João Rodrigues Calbrilho and his crew abandon what is now California?

When João Rodrigues Calbrilho, a Portuguese explorer, arrived with his crew in California in the early 1500s (they were the first Europeans to do so), the crew abandoned the place, thinking it was too isolated from the world's other trade points.

Explanation:

the answer would be choice c, cave paintings.

disease was the number one killer of native peoples. they had had little exposure to the diseases of europe. this led to some villages being almost completely wiped out and some tribes destroyed.