题目

阅读理解In the middle of the 19th century, a fever dream of riches beyond measure drew countless explorers west to the mountains of central California. Although the gold rush ended up being a bust_for many who sought a fortune, some of those explorers discovered a natural treasure that would draw permanent settlers to Yosemite Valley in the following decade.Vast wilderness, beautiful mountains, countless waterfalls, and abundant wildlife drew Native Americans to Yosemite roughly 10, 000 years ago. The first non­native tourists arrived in the mid­1850s after reports from gold seekers told下列粒子中，能决定元素种类的是A.质子数B.中子数C.核外电子数D.相对原子质量