Answer: Option B
The oil crisis in the 1970s was a seminal event that brought the issue of energy security and the need for alternative sources of energy to the forefront of global discourse. The crisis was a result of the OPEC (Organization of the Petroleum Exporting Countries) embargo on oil exports to countries that supported Israel in the Yom Kippur War. This resulted in a significant shortage of oil, which led to widespread panic, high inflation, and long lines at gasoline stations.
The oil crisis highlighted the importance of developing new sources of energy to reduce dependence on oil and ensure energy security. The following are the key points that explain why "sources" is the correct answer:

• Energy security: Developing new sources of energy would reduce the dependence on a single energy source, such as oil, and enhance energy security. This would help mitigate the impact of future energy crises.

• Alternative sources of energy: The oil crisis showed the need to develop alternative sources of energy that are sustainable, renewable, and have a lower environmental impact. For example, the use of solar, wind, hydro, and nuclear energy sources can help reduce dependence on oil.

• Conservation of energy: Developing new sources of energy alone is not enough. It is also important to conserve the energy sources that are already in use. This can be done through energy efficiency measures, such as the use of energy-efficient appliances and buildings, and reducing waste.

In conclusion, the oil crisis of the 1970s brought the issue of energy security and the need for alternative sources of energy to the forefront. The correct answer is "sources," as developing new sources of energy is crucial for reducing dependence on a single energy source, enhancing energy security, and promoting sustainability.