Which of the following represents the longest duration of geologic time?

A) Jurassic
B) Precambrian
C) Paleozoic
D) Mesozoic
E) Cenozoic

Precambrian time covers the vast bulk of the Earth's history, starting from the formation of the Earth about 4.6 billion years ago and ending approximately 541 million years ago with the start of the Cambrian Period. It represents the longest duration of geologic time, encompassing the Hadean, Archean, and Proterozoic eons, which is significantly longer than the time spans covered by the Jurassic (a period within the Mesozoic Era), Paleozoic, Mesozoic, or Cenozoic eras.