The term 'epidemiology' is derived from which language?

Correct Answer: B

Rationale: Epidemiology' comes from Greek: 'epi' (upon), 'demos' (people), and 'logos' (study), meaning the study of what happens to people (B). Latin (A), French (C), and German (D) are incorrect origins.

Correct Answer: D

Rationale: Randomized controlled trials (D) assign interventions randomly to test effects (e.g., drug trials). A, B, and C are observational.

Correct Answer: A

Rationale: Secondary attack rate (A) measures infection among contacts of a primary case (e.g., household spread). B, C, and D are broader or vague.

Correct Answer: B

Rationale: Cross-sectional studies (B) measure prevalence at one time (e.g., obesity rates). A requires time, C and D need longitudinal data.

Correct Answer: B

Rationale: Descriptive studies (B) collect quantitative data (e.g., case counts) to describe patterns. A is qualitative, C is experimental, D is broad.