Answer: A the chromosomes from another parent cell were introduced
Explanation: A child is created when the male sex cell joins the female cell. If the male and female sex cells had the standard number of chromosomes, as is found in body cells then the zygote (baby) would have double that number of chromosomes. The number of chromosomes would keep doubling every generation. To avoid this doubling the parent's body cells split by miosis which halves the number of chromosomes and so when the sex cells join the total number of chromosomes is the same as that found in the parent's body cells.
Brain size has increased nearly 3x in 4 million years.
The type of stimulus following a behavior removes something that is unpleasant is the negative reinforcer.
Stimulus is any signal. This can be in the form of touch, smell, taste, etc. This stimulus triggers the nerve cells of the body that send to signals to the brain to generate a response. For example, when one person touches a hot utensil, the touch of heat acts as a stimulus, where the brain sends response in the form of instantly removal of the hand.
Negative reinforcement is the response towards a stimuli that has not yet been received. For example, taking a medicine before any disease appears is the acts of negative reinforcement.
To know more about negative reinforcement, here
brainly.com/question/14299460
#SPJ4
Hshsjsndhsnjsmsnzjsnsjsnjsnsjsn
A