Four events that result in the greenhouse effect are resulted below:
I. Earth reflects a part of sunlight
II. Trapped radiation heats up the atmosphere
III. The Earth's atmosphere traps the reflected sunlight.
IV. Sunlight falls on the surface of the Earth.
Which arrow diagram correctly represents the sequence of events that result in the greenhouse effect?

Options

A. `I to II to III to IV`
B. `I to IV to III to II`
C. `IV to III to II to I`
D. `IV to I to III to II`

Answer

To determine the correct sequence of events that result in the greenhouse effect, we need to arrange the four events logically. Here’s the step-by-step solution:

### Step-by-Step Solution:

1. **Identify the Events**: The four events given are:
- I. Earth reflects a part of sunlight.
- II. Trapped radiation heats up the atmosphere.
- III. The Earth's atmosphere traps the reflected sunlight.
- IV. Sunlight falls on the surface of the Earth.

2. **Determine the Starting Point**: The greenhouse effect begins when sunlight reaches the Earth. Therefore, the first event in the sequence is:
- **IV. Sunlight falls on the surface of the Earth.**

3. **Next Event**: After sunlight reaches the Earth, a portion of that sunlight is reflected back into space. Thus, the second event is:
- **I. Earth reflects a part of sunlight.**

4. **Third Event**: The sunlight that is not reflected is absorbed by the Earth’s surface, which then warms up. The heat from the Earth is radiated back towards space, but some of it is trapped by greenhouse gases in the atmosphere. Therefore, the third event is:
- **III. The Earth's atmosphere traps the reflected sunlight.**

5. **Final Event**: The trapped radiation leads to an increase in temperature in the atmosphere. Hence, the final event is:
- **II. Trapped radiation heats up the atmosphere.**

6. **Final Sequence**: Putting it all together, the correct sequence of events that lead to the greenhouse effect is:
- IV → I → III → II

### Conclusion:
The correct arrow diagram representing the sequence of events that result in the greenhouse effect is:
- **IV (Sunlight falls on the surface of the Earth) → I (Earth reflects a part of sunlight) → III (The Earth's atmosphere traps the reflected sunlight) → II (Trapped radiation heats up the atmosphere)**.