The answer is B - Thymine
Explain : because a , c , d are not nucleotides
I hope that's help !
I think it might be <em>natural disasters.</em>

Damage to the frontal lobe of the braineventually causes problems with intelligence, judgment, and behaviour. Damage to the temporal lobe affectsmemory. And damage to the parietallobe affects language. Alzheimer's is themost common form of mental decline, or dementia, in older adults.
Answer:
Explanation:
hepatic portal vein is a blood vessel that carries blood from the gastrointestinal tract and spleen to the liver. This blood are usually rich in nutrient because it contains extraction from digested materials or food substances in the gastrointestinal tract and it is processed in the liver for removal of toxins before the blood returns to the heart.