A method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.
B is the answer. That is the brain
A. 12 chromosomes, because sex cells (gametes) are haploid, meaning they only have one copy of each chromosome
Hemoglobin causes the substance to form long rods in the red blood cell as the hemoglobin releases oxygen