Answer:
Autism
Explanation:
Description from the passage from your question is telling us that seems that Liam has autism. Sometimes it is hard to recognize it at that age because Liam is only two years old.
The children that have autism don't like to be touched and they don't like to make eye contact with anyone.
The third option I’m sorry if I’m wrong
Instead of using animals in medical expereince, i think<< that scientests could test it on bacteria or humans, if it is safe enough.
Cerebrospinal fluid (CSF), clear, colourless liquid that fills and surrounds the brain and the spinal cord and provides a mechanical barrier against shock. Formed primarily in the ventricles of the brain, the cerebrospinal fluid supports the brain and provides lubrication between surrounding bones and the brain and spinal cord. When an individual suffers a head injury, the fluid acts as a cushion, dulling the force by distributing its impact. The fluid helps to maintain pressure within the cranium at a constant level.
https://www.britannica.com/science/cerebrospinal-fluid