The greatest revenue earning industry in Nigeria is

The greatest revenue earning industry in Nigeria is oil and gas, which falls under the category of mining. Nigeria is one of the largest oil-producing countries in Africa and the world. The oil and gas industry has played a significant role in the country's economy, contributing a substantial percentage to the Gross Domestic Product (GDP) and serving as a major source of foreign exchange earnings. The industry also provides employment opportunities and is a major driver of infrastructural development in the country.