The Change from Thinking the Continents Are Stationary to Understanding

Multiple Choice

The change from thinking the continents are stationary to understanding that the outer layer of the earth moves slowly nearly all of the time occurred primarily because_______ .

A) we had two world wars and learned a lot from them about the oceans that explained how continents moved
B) we got space travel and could see the motions
C) we began to make global observations that required recognition that the continents and oceans had not always been in their current positions
D) we improved our surveying instruments significantly