A record of Earth's long-ago weather can be found by digging into the
A
polar ice cap in Antarctica.

B
lava from volcanoes.

C
sand bars in tropical waters.

D
melting permafrost in Alaska, Canada, and Siberia.

Option A.

Polar ice cap in Antarctica.

Explanation:

Scientist drill ice cores from inside the polar ice cap in Antarctica to study variability of climate and differentiate that variability From global climate change. Each layer of the ice tells about weather and what the Earth was like when the first snow fell.

For example, Le grande says that as snow deposits into a growing glacier, the temperature of the air imprints on water molecules.

Icy layers hold particles,aerosols, sea salts, trace elements that were in the atmosphere before and they abide for thousands of years and provide evidence of past events.

hormones in blood stream

image: dtc.ucsf.edu

endocrine glands secrete hormones into the blood stream near them; the hormones then travel in our bloodstream until it reaches its destination, called a target cell, in distance parts of the body. in the target tissue, hormones lock onto the target’s plasma membrane, called the receptor site.