Oxygen supports burning (combustion). In a similar scientific analogy, carbon dioxide has which opposite effect on fire?

Introduction / Context:
This analogy question links basic science with verbal reasoning. The pair Oxygen : Burn reminds us that oxygen gas supports burning or combustion. In the second part Carbon dioxide : ? we have to identify what carbon dioxide does in relation to fire. The question checks whether you understand that different gases have opposite effects on combustion and can either support or suppress a flame.

Given Data / Assumptions:

• Oxygen is essential for combustion and supports burning.
• Burn refers to the process of combustion or fire.
• Carbon dioxide is another common gas used in fire safety equipment.
• The options are Extinguish, Explode, Isolate, and Foam.
• We assume basic school level knowledge about how fire extinguishers work.

Concept / Approach:
Combustion needs three main elements: fuel, heat, and oxygen. Oxygen helps a fire to keep burning, so Oxygen : Burn indicates a supportive relationship. Carbon dioxide behaves very differently. It does not support combustion. Instead, it is used in many fire extinguishers because it pushes away oxygen and cools the flame. When carbon dioxide is released onto a fire, it helps to extinguish the flames. Therefore the parallel relationship is Oxygen : Burn as supporting fire and Carbon dioxide : Extinguish as putting fire out.

Step-by-Step Solution:
Step 1: Understand that oxygen supports burning and is part of the fire triangle. Step 2: Recognise that the first pair shows a gas and its main effect on fire. Step 3: Recall that carbon dioxide is widely used in fire extinguishers. Step 4: Know that when carbon dioxide is released onto flames, it displaces oxygen and cools the burning material. Step 5: Conclude that the best word to describe this effect is extinguish, meaning to put out the fire. Step 6: Match Oxygen : Burn with Carbon dioxide : Extinguish as opposite roles in combustion.

Verification / Alternative check:
We can verify by thinking about real fire safety equipment. Carbon dioxide fire extinguishers are standard for electrical fires and some liquid fires. They work by blanketing the fire with carbon dioxide gas so that oxygen cannot reach the burning surface. Without enough oxygen, the flames die out. The word explode describes a rapid violent expansion and is not a normal effect of carbon dioxide on fire. Isolate and Foam are more general or refer to another type of fire extinguisher that uses foaming agents, not directly to carbon dioxide gas. So Extinguish remains the only clear, correct match.

Why Other Options Are Wrong:
Explode: Carbon dioxide does not normally cause explosions in the context of fire control; it is used to stop burning, not to increase its violence.
Isolate: While carbon dioxide helps separate fire from oxygen, the more precise effect in this analogy is extinguishing the flames, not simply isolating them.
Foam: Foam refers to another physical substance used in some extinguishers. It is not carbon dioxide itself and therefore does not correctly complete this gas based analogy.

Common Pitfalls:
A common mistake is to pick a word that sounds strong, such as explode, without checking whether it actually describes the gas. Another pitfall is confusion between different types of fire extinguishers, such as foam and carbon dioxide models. Remember that oxygen and carbon dioxide have opposite roles in fire behaviour: oxygen feeds fire, while carbon dioxide helps to put it out. Keeping that contrast in mind makes Extinguish the obvious answer.

Final Answer:
Oxygen supports burning, while carbon dioxide is used to extinguish fire, so Extinguish is the correct completion of the analogy.