Annie Is a 3-Month-Old Infant

question 103

Multiple Choice

Annie is a 3-month-old infant.Which behavior has probably just appeared?

• A) distress
• B) laughter
• C) social smile
• D) fear

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Definitions:

Autosomes

Chromosomes that are not sex chromosomes and are present in pairs in both males and females, making up the majority of the human genome.

Sex Chromosomes

Chromosomes that determine an individual's sex, with females typically having two X chromosomes and males having one X and one Y chromosome.

Indolamine

A type of neurotransmitter which includes serotonin, involved in the regulation of mood and behavior.

DNA

Deoxyribonucleic acid, a molecule that carries the genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and many viruses.