Which is an example of dehydration synthesis?
dna synthesis from nucleotides
conversion of proteins into its amino acids
conversion of lipids from fatty acids

The right answer is DNA synthesis.

In chemistry, a dehydration reaction is a chemical reaction in which the starting reagent loses a hydrogen atom and a hydroxyl group, a molecule of water, the reverse of the hydration reaction. Dehydration reactions are a subset of the elimination reactions.

In the case of DNA synthesis:

d (NTP) n + dNTP -> d (NMP) n + 1 + PPI + H2O

explanation:

for  example, forests have higher evapotranspiration than other ecosystems,  such  as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.