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:
Sexual selection
Explanation:
It is sexual selection because it is a type of natural selection in which an organism or organisms acquire traits which help the individual to be choose as a mating partner or to have preference for a mating partner or for competition among one sex organisms in which a traits succeed.
Sexual selection can be intrasexual or or intersexual. Intrasexual is is competition between one sex of the same organism and intersexual is between sexes of different organism.
I think it is D but I might be wrong !!! Hope I help !!
