When developmentalists looked at the two kinds of intelligence, fluid and crystallized, to determine if intelligence continues to grow, slow, or decline with age, they determined that ) fluid intelligence does decline; however crystallized intelligence holds steady and can improve(b) crystallized intelligence does decline; however, fluid intelligence holds steady and can improve(c) both fluid and crystallized intelligence decline with age(d) both fluid and crystallized intelligences improve with age

Developmentalists determined that: (A) Fluid intelligence does decline; however crystallized intelligence holds steady and can improve

Explanation:

This theory of intelligence classifies two types of intelligence, based on the processess each one requires. Fluid intelligence is about being able to reason, to make predictions or asumptions, to make logical connectios. This intelligence does not involve previous experience, or studies.

While by the other hand there is crystallized intelligence, they state elderly people developed this type of intelligence because of previos experience, acumulation of knowledge. This is a type of intelligence that is cultivated in time and does is why it can impove.

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