The oil crisis highlighted the need to develop new . . . . . . . . of energy and to conserve those which are already in use.

methods
sources
means
preserves

The correct answer is: B. sources

The oil crisis highlighted the need to develop new sources of energy and to conserve those which are already in use.

  • Methods are ways of doing something. For example, one method of conserving energy is to turn off lights when you leave a room.
  • Means are ways of achieving something. For example, one means of conserving energy is to use energy-efficient appliances.
  • Preserves are places where things are kept safe and protected. For example, a national park is a preserve where animals and plants are protected.

The oil crisis was a period of time in the 1970s when the price of oil increased significantly. This caused a lot of problems for many countries, as they relied on oil for energy. The oil crisis highlighted the need to develop new sources of energy, as well as to conserve the ones that were already in use.