What Appears in an Infant Between 2 and 4 Months

question 171

Multiple Choice

What appears in an infant between 2 and 4 months of age?

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

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Definitions:

Barely Perceptible

Something so slight or minimal that it is almost impossible to notice or detect.

Light Waves

The form in which light travels, consisting of oscillating electric and magnetic fields, which allows it to propagate through various mediums, including a vacuum.

Amplitude

The height of a wave from the middle to the crest (top) or trough (bottom), measuring the strength or intensity of the wave.

Shorter

Having lesser length, height, or duration than something else or than is typical.