Which of the Following Statements Best Describes the Mechanism(s)by Which

question 29

Multiple Choice

Which of the following statements best describes the mechanism(s) by which venous blood returns to the heart?

• A)Intraluminal valves ensure unidirectional flow toward the heart.
• B)Contracting skeletal muscles milk blood distally toward the veins.
• C)The high-pressure system of the heart helps to facilitate venous return.
• D)Increased thoracic pressure and decreased abdominal pressure facilitate venous return to the heart.

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Definitions:

External Cost

Costs that a producer or consumer inflicts on a third party who is not involved in the production or consumption of the goods or services.

Economic Efficiency

A situation in which all resources in an economy are optimally distributed to serve each individual or entity in the best way while minimizing waste and inefficiency.

Competitive Market

A competitive market is a market structure characterized by a large number of buyers and sellers, where no single entity has the power to influence market prices significantly.

Free-rider Problem

A situation where individuals benefit from resources, goods, or services that they do not pay for, which can lead to underproduction or depletion of those resources.