Comparative with a wide range of variables
I think the best answer is D. It is thought that advances such as agriculture, literacy, and urbanization have not been accompanied by additional increases in brain size because the physiological cost of a bigger brain exceeds its benefit. The brain requires a lot of nutrients to function. Having a bigger brain would cost a lot rather than benefiting from it.
Answer:
False
Explanation:
In DNA double helix molecule, there are four types of nitrogenous bases: adenine, guanine, cytosine and thymine. Purines (i.e., adenine, guanine) and pyrimidines (i.e., cytosine and thymine) hold DNA strands together via hydrogen bonds. In base pairing, guanine always pairs with cytosine through 3 hydrogen bonds, while adenine always pairs with thymine by 2 hydrogen bonds. Hydrogen bonds are a type of dipole–dipole interaction where a hydrogen atom is covalently bonded to a very electronegative atom (e.g., Nitrogen or Oxygen).
