Final answer:
Britain turned to oil and gas as its coal deposits were used up. This shift occurred as coal became less feasible due to depletion of reserves and the emergence of alternative energy sources like North Sea oil.
Step-by-step explanation:
As coal deposits were used up, Britain turned to: C) Oil and gas. Coal was an essential resource for the Industrial Revolution in Britain, due to its ability to produce significant amounts of energy for heating and powering machinery. However, as Britain's forests were depleted to the point where wood imports became necessary, and former prejudices against coal were overcome, the nation moved towards coal usage.
With the advent of industrialization, coal became a major energy source, peaking around 1850. As coal reserves began to dwindle, the United Kingdom shifted its focus to other energy sources, including oil and natural gas. These new sources of energy became more prominent, especially after North Sea oil extraction began, reducing reliance on coal as a primary energy source.