The cardiovascular system, which transports blood through the body, is a one-way system.
a. true
b. false

The correct answer will be option-False

Explanation:

The cardio-vascular system is the system of the vascular tissues of the human body connected to the cardiac system or the Heart.

The heart specializes in pumping the oxygenated blood to the body through these vascular tissues which are required by the cells to complete the cellular respiration. The process of respiration makes the blood deoxygenated and must be then carried back to the heart without the pressure applied by the heart.

This oxygenated-deoxygenated flow of blood throughout the body thus forms the two-way system and therefore, false is the correct answer.

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).   so the answer is a.