Which of these diagrams best represents the steps in the formation of planets?
a) the sun is born > the clouds rotate at high speed > the clouds flatten into an elliptical disc > the planets are born
b) the clouds flatten into a disc > the sun is born > the clouds condense > the planets are born
c) the clouds of dust and gases rotate at high speed > the clouds condense > the sun is born > the planets are born
d) the clouds of gases condense > the clouds rotate at high speed > the clouds flatten into an elliptical disc > the planets are born