I believe it is ¨there is a shortage of 2,000 bikes¨ because if they demand 8,000 bikes but only make 6,000 bikes there is a shortage of 2,000 bikes
Option A is the right answer.
Began around 10,000 B.C, the Neolithic revolution in the history of Human marks the transition from small nomadic bands of hunter-gatherer to larger agricultural settlement and early civilization. People in the Paleolithic age used Primitive stone tools, whereas tools in the Neolithic era were more sophisticated. People during this age invented new types of tools such as sickle blades and stone axes etc. People in the Paleolithic age lived in small groups of 20- 30 people in caves, or in cabins made of tree branches, while, the Neolithic people with the advent of agriculture and raising cattle moved to settle as the farmers and villagers.
A and b I believe are correct
