According to the passage, one result of the oil crisis caused by the Arab-Israel war has been that -----.

The great expansion in energy demand over recent years has
been met to a large extent by petroleum oil. The total world
reserves of petroleum oil are still uncertain since large parts of
world are still not fully prospected. The cutback in oil
production and the rise in the price of Middle Eastern oil
following the 1973 Arab-Israel war unleashed a worldwide
energy crisis. The result has been that Britain has increased its
north sea oil production and has become the fifth largest oil
producing country in the world.