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:

Historical Experience

The collected information and insights gained from past events and activities, which can inform current decision-making and strategic planning.

Allowance Factor

A factor used in planning and scheduling to accommodate potential variances or uncertainties, typically by adding extra time or resources.

Standard Time

The predetermined amount of time allocated for completing a specific task, taking into account normal delays and work pace.

Normal Time

An estimate of the average time in which a task or operation can be completed, considering the typical pace and conditions.