Since Observational Independent Variables Will Always Be Confounded with All

question 103

Multiple Choice

Since observational independent variables will always be confounded with all other variables that are naturally related to them,_____ are typically not possible when an observational strategy is used.

• A)experimental manipulations
• B)correlated observations
• C)statistical analyses
• D)causal inferences

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Definitions:

Hepatic Portal Vein

The hepatic portal vein is a blood vessel that carries blood from the gastrointestinal tract and spleen to the liver, transporting nutrients and toxins for processing.

Saphenous Vein

A large vein running along the length of the leg, often used for grafts in coronary artery bypass surgery.

Popliteal Vein

A vein located behind the knee that drains blood from the lower leg to the thigh.

Femoral Vein

A major vein in the thigh that returns deoxygenated blood to the heart from the lower limbs.