Characteristics of a Good Fuel:
A good fuel possesses certain characteristics that make it suitable for use. These characteristics include high energy content, availability, ease of storage and transport, safety, and environmental friendliness. Based on these characteristics, the correct answer to the question is option 'b' - Butane.

Explanation:
Butane is a hydrocarbon fuel that is commonly used for various purposes. Here are the reasons why butane possesses the characteristics of a good fuel:

1. High Energy Content:
Butane has a high energy content, which means it can release a significant amount of heat when it undergoes combustion. This makes it an efficient fuel for various applications, such as heating, cooking, and powering engines.

2. Availability:
Butane is readily available in the market. It can be easily obtained in the form of liquefied petroleum gas (LPG) cylinders, making it convenient for residential and commercial use.

3. Ease of Storage and Transport:
Butane is a highly compressed gas when stored, but it can be easily converted into a liquid form under moderate pressure. This makes it easy to store and transport in cylinders or tanks without the need for complex infrastructure.

4. Safety:
Butane is considered a safe fuel to use due to its low toxicity and non-toxic combustion products. It has a narrow range of flammability, requiring specific conditions for ignition. Additionally, it has a distinct odorant added to it to detect leaks easily.

5. Environmental Friendliness:
Compared to other fossil fuels, butane is relatively cleaner-burning. It produces fewer emissions of pollutants, such as sulfur dioxide and particulate matter, which contribute to air pollution and respiratory problems. However, it is still a hydrocarbon fuel and emits carbon dioxide when burned, contributing to greenhouse gas emissions and climate change.

In conclusion, Butane possesses the characteristics of a good fuel due to its high energy content, availability, ease of storage and transport, safety, and relatively cleaner-burning nature. These qualities make it a suitable choice for various applications, especially in residential and commercial settings.