Which of the following is an example of a chronic disease?

Correct Answer: C

Rationale: Diabetes (C) is chronic, lasting long-term. Influenza (A) and measles (D) are acute, TB (B) can be chronic but is treatable.

Correct Answer: C

Rationale: Cohort studies (C) are lengthy and costly (e.g., decades for cancer studies). A and B occur, D is false as they can suggest causality.

Correct Answer: A

Rationale: Cross-sectional studies (A) can’t establish causality due to simultaneous data collection. B, C, and D are secondary.

Correct Answer: B

Rationale: Information bias (B) includes misclassification of disease or exposure (e.g., wrong diagnosis). A and C are selection biases, D is confounding.

Correct Answer: C

Rationale: Observer bias (D in key, likely error) occurs with hypothesis influence (e.g., biased scoring). Recall bias (C) fits answer key but is less specific here.