Some hunter-gatherer groups for whom we have ethnographic records,

a. believed that overhunting would anger deities
b. killed large numbers of animals only every several years
c. were not especially concerned with conservation
d. all of these

option D

Explanation:

Ethnographic relates to the scientific study of specific human cultures and societies.

Cultures & traditions are held in several parts of the world, from Africa to South America to Asia so. on.

Most hunter-gatherer groups had

I) LITTLE belief in preserving natural resources, because they basically LIVED for sustenance, and even organized COMPETITIONS to reward the Hunter with the MOST KILL OR HUNTED ANIMALS

II) belief that overhunting would anger deities, as some animals like CROCODILES are considered SACRED and should not be hunted.

III) belief that hunting (like fishing) in some rivers should be seasonal or periodic like ONCE in four years etc

So, ethnographic records will actually have all of the options A, B, and C

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