Which of the Following Statements Is the Best Example of an Hypothesis

Which of the following statements is the best example of an hypothesis about human development?

A) All the children in the high-scoring group were breast-fed as infants, which explains their higher levels of achievement.
B) If breast milk is a superior supplement for infant brain development, then on psychological tests, children who were breast-fed as infants should perform better than children who were not breast-fed as infants.
C) Human breast milk contains nutrients that are essential for the formation of neurons and synapses in an infant's developing brain.
D) Cross-cultural studies have determined that human breast milk provides the ideal nutrition for infant brain development.