Which of These Statements About Cholesterol Synthesis Is True

Which of these statements about cholesterol synthesis is true?

A) Cholesterol is the only known natural product whose biosynthesis involves isoprene units.
B) Only half of the carbon atoms of cholesterol are derived from acetate.
C) Squalene synthesis from farnesyl pyrophosphate results in the release of two moles of PP_i for each mole of squalene formed.
D) The activated intermediates in the pathway are CDP-derivatives.
E) The condensation of two five-carbon units to yield geranyl pyrophosphate occurs in a "head-to-head" fashion.