A volcanic eruption took place about two billion years ago and released lava onto Earth's surface. The lava cooled to form basalt. Which of the following is least likely to have happened to the basalt over this time?
Some of the basalt melted and became molten rock.
Some of the basalt changed into metamorphic rock.
Most of the basalt stayed the same for two billion years.
Most of the basalt broke down and became sediment