Question

why is the dogs always produce several puppies for as humans usually produced only one child at a time

Answer 1

Dog releases many eggs at a time and they are fertilized by sperms which produces multiple puppies

Answer 2

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Dogs produce more than one egg at a time. All these eggs get fertilized and hence more than one babies are born to them at the same time.

On the contrary human female produce only one egg at a time thus normally only one baby at a time.

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