Final answer:
Vision becomes an infant's dominant sense at around six months, with near-adult levels of acuity, color recognition, and the beginnings of depth perception.
Step-by-step explanation:
The dominant sense in an infant at around six months is vision, which has developed significantly by this age. Infants at this stage can pick up objects, transfer them from hand to hand, and even pull themselves into a sitting position. Their vision is nearly as acute as that of an adult, with the ability to notice colors and the beginnings of depth discrimination. It's important to note that while newborns possess a surprising array of sensory abilities, their vision is initially the least developed. However, by around six months, vision has improved to be almost as sharp as an adult's.