Which task would primarily require fluid intelligence?

Fluid intelligence refers to the capacity to reason and solve new problems independently of previously acquired knowledge. It involves the ability to think logically and identify patterns in novel situations, as well as adapt to unfamiliar problems or environments.

Solving a new type of puzzle exemplifies fluid intelligence because it requires the individual to apply reasoning and deduction skills without relying on prior knowledge or experiences specific to that particular puzzle. It challenges one's ability to think abstractly and creatively while determining the solution.

Other tasks mentioned, such as solving a math problem or memorizing vocabulary, involve more crystallized intelligence, which is based on knowledge and skills acquired through experience and education. Understanding a historical text similarly relies on background knowledge and comprehension skills rather than the ability to solve novel problems. Therefore, the task of solving a new type of puzzle stands out as one that primarily taps into fluid intelligence.