How did english language spread in nigeria?

Effectively the correct answers are:

1. Algeria - It fought a long and costly war for liberation form France. In this case, the FLN (Front de Libération Nationale) leaded a civil war against against France. Mainly this war and anticolonialism feeling had origin after WWII in which many Algerians helped France, but after the war they weren't treated the same way than those who left in Metropolitan France.

As well as that, it is possible to say that it was a long and costly war because France was ready to lose any other African territory, excepting Algeria. At the end, this generated in high efforts by France that represented difficulties for Algeria, leading to time and large money.

2. Ghana - It was named after an ancient African kingdom. In 1957 Ghana was the first Colony that reached independence. Because of this, leaders decided to take a name that represented quite power and at the same time  were highly related to Africa. For those reasons, they chose GHANA as an ancient empire that wasn't located in the countries land (it was more in what we know as Mali), but that was recognized by its economical power through the Sahara.

3. Democratic Republic of Congo - It had a civil war between the national government and Katanga province. The Democratic Republic of Congo was originally controlled by Belgium. Nevertheless, in the rich south region, Katanga, people revolted against Belgium power and even other tribes in the country. At the end, it generated not only the independence of the whole Republic, but a long civil war in the now independed country and many other problems that can be traced until today.

4. Kenya - The Mau Mau rebellion led to its eventual independence from Great Britain. Mau Mau was a guerilla that fought against the Great Britain since 1952. Their obtective was basicly the Kenyan independence that they reache in 1960.