I also believe the answer is A.
The correct answer is: the treated glioblastoma cells were cultured in the presence of an inhibitor from umbilical cord stem cells, but the control cells were cultured without the inhibitor.
It has been shown that treatment with injected umbilical cord stem cells has strong therapeutic effects on glioma models. Those cells produce anti-tumour substances, with inhibitory effects.
Control group does not include the treatment in order to observe the treatment.
Answer:
Bipedalism freed the hands so they could be used to cart food, make and use weapons and other advantages of freed hands. Bipedalism is a much more efficient way to walk and run and this fact is quantified. Bipedalism raised the early proto-human above the horizontal so he could see predators approaching. Bipedalism is a much more efficient design to cool down overheating bodies.
your welcome :)
Around 3-4% is the answer.