When a trait is shown and at least one letter is upper case. A) dominant
B) recessive
C) trait
D) allele

When a trait is shown and at least one letter is upper case, it is a dominant allele (option A).

Explanation:

In genetics the presence of a dominant allele - represented by a capital letter - is sufficient to suppress a recessive allele, expressing the dominant trait in the phenotype.

Dominance is based on allelic combinations of the genotype, which are expressed in the phenotype for a given characteristic:

The other options are not correct, because:

    B) Recessive  is the allele that is only expressed in the phenotype when there is a pair in the gene.

    C) Trait  is equivalent to a characteristic.

    D) Allele represents the different ways in which a gene is expressed.

brain development. a child's brain undergoes an amazing period of development from birth to three—producing more than a million neural connections each second. the development of the brain is influenced by many factors, including a child's relationships, experiences and environment.

explanation:

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