Science Assessment ~ Topics ~ Plate Tectonics ~ Item PT025001 ~ Student Performance

Which of the following is TRUE about the movement of earth’s plates?

They do not move because they sit on a layer of solid rock.
They move along with the layer of slightly softened rock below them.
They move by floating on a layer of completely melted rock below them.
They do not move until the solid rock layer beneath them temporarily melts and moves.

Distribution of responses
Answer Choice		Overall	Grades		Gender		Primary Language
		n = 1475	6–8 n = 971	9–12 n = 496	Male n = 698	Female n = 753	English n = 1336	Other n = 100
A.	They do not move because they sit on a layer of solid rock.	6%	6%	5%	6%	6%	6%	6%
B.	They move along with the layer of slightly softened rock below them.	37%	38%	36%	35%	40%	36%	48%
C.	They move by floating on a layer of completely melted rock below them.	35%	33%	38%	39%	31%	35%	26%
D.	They do not move until the solid rock layer beneath them temporarily melts and moves.	22%	22%	21%	20%	23%	22%	20%

Science Assessment