What element is commonly used to date archaeological or geological materials? Select one:
a. Phosphorus
b. Nitrogen
c. Hydrogen
d. Carbon

D. Carbon

Explanation:

Carbon is the element that is commonly used to date fossils and ancient materials.

This is called carbon dating, where the concentrations of different carbon isotopes are used to determine the age of ancient materials.

Carbon dating has been used for almost 70 years and is still commonly used to date fossils.

So, the correct answer is D. Carbon

step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.

currents is the correct answer.