Cause & Effect — Popularity of a beverage.\nI. Coffee contains caffeine, a stimulant that raises energy levels and can induce sleeplessness.\nII. Coffee is a popular drink with office workers across the world.

Introduction / Context:
This problem asks whether a pharmacological property (caffeine’s stimulation) provides a direct explanation for a social fact (popularity among office workers).

Given Data / Assumptions:

• I: Coffee’s active component (caffeine) increases alertness and can delay sleep.
• II: Coffee is widely popular among office workers globally.
• Office work often demands sustained attention and wakefulness.

Concept / Approach:
Link the functional attribute to the user need: alertness for productivity. That makes I a plausible immediate cause for II.

Step-by-Step Solution:

Verification / Alternative check:
Even if taste, habit, or culture also matter, the stimulant property provides a clear proximate reason for office popularity.

Why Other Options Are Wrong:
Options B/C/D misstate direction or deny the obvious functional link.

Common Pitfalls:
Demanding exclusivity of cause; multiple reasons can exist, but I remains an immediate cause.

Final Answer:
If I is the immediate cause and II is its effect.