Cambrian seas A. were at an all-time low level during the whole of the period. B. rarely encroached on the land and thus marine deposits are rare. C. did not cover much land area due to continued orogenic activity. D. were widespread due to many low-lying land masses.

D. were widespread due to many low-lying land masses.

Explanation:

Cambrian Period was the first geological period of the Paleozoic Era, it occurred between two ice ages; Proterozoic and Ordovician. During these era, there were mass extinctions due to the decrease in global temperature.

Cambrian seas were widespread due to many low-lying land masses.

answer; ///i believe that the correct answer is (b) cold and high