单项选择题

What causes differences in size and color of annual rings

A．The climate.
B．The exposure to light.
C．The length of time.
D．The fertility of the soil.
<上一题 目录 下一题>
热门 试题

单项选择题
What happens to trees each year
A．Their tings get thinner and thinner.
B．They add a ring of wood.
C．Their rings get darker in color.
D．They become more valuable.
单项选择题
When did dendrochronology begin to interest archaeologists
A．It began 2000 years ago.
B．It began in the eighteenth century.
C．It began in the early twentieth century.
D．It began in this decade.
相关试题