a chemical element or substance required in trace amounts for the normal growth and development of living organisms.
I think the correct answer would be the second option. The group of archaebacteria would be found on the lowest branch of a phylogenetic tree of all life. Phylogenic trees are illustrations of a hypothetical evolution of the organisms and its relationship with the other organisms. From the listed options, the archaebacteria is most likely to be the most basic and simplest life form. It should be placed before the other options so at the lowest branch. This illustration is being used by scientists to describe how evolution and the connection of the organisms came about. It sometimes called as the tree of life.
The correct answer is (b)The vestibular sense may be capable of sensory adaptation
Astronauts experience similar feelings of dizziness and disorientation upon arrival in space and upon their arrival back on Earth because the vestibular sense may be capable of changing adaptation. The dizziness and disorientation is due to the floating fluid in inner ear around zero gravity and it goes right away after some time when the astronauts reach the space. The adaptation is done by the brain to ignore the signals of the ear; the feeling this sensation for sometime the brain becomes adaptable and does not listens to the inner ear every time. This is a kind of sensory adaptation.
