For those actually in relationships, shyness was negatively associated with intimacy satisfaction. Shyness was also positively associated with insecure romantic attachments, including greater attachment anxiety and attachment avoidance. For males especially, shyness also had a negative relationship with overall psychological well-being.
The stage at which the development of the brain reaches its adult is the middle childhood. A child's Brain undergoes a period of development from birth to three-producing more than a million neural connections each second. This development is influenced by many factors, which include the child's relationships, experiences and environment.
The answer is; B
Mutation is one source of variation (in addition to sex and gene flow). Mutations are rare and occur in a small proportion of individuals. However, due to the advantage that the genetic mutation confers to these individuals, their chances of passing the genes to the next generation is higher than that of the general population.
This way, the allelic frequencies of these advantageous mutated genes increase with each generation and eventually become the majority population over time.