It Is Difficult to Establish the Causal Link Between Cigarette

question 3

Multiple Choice

It is difficult to establish the causal link between cigarette smoking and lung cancer because

• A) random allocation of subjects to smoking is unethical.
• B) observational studies generally cannot rule out confounding.
• C) those who choose to smoke may be genetically at greater risk for lung cancer than those who don't choose to smoke.
• D) experiments done on animals may not be valid for humans.
• E) All of the above

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Definitions:

Genetic Imbalance

A condition where there is a discrepancy in the number or structure of chromosomes, often leading to developmental issues or diseases.

Amniocentesis

A medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, involving the extraction of amniotic fluid using a syringe.

Chorionic Villus Sampling

A prenatal test in which a sample of chorionic villi is taken from the placenta for genetic testing.

Gene Therapy

A medical technique that involves modifying or repairing defective genes to treat or prevent disease.