Problem: David works as a nutritionist with the public health department. He categorized the certain sections of his county's population. First he categorized boys and girls between nine and thirteen years as cat A. Then he put girls between fourteen and eighteen years in cat B, and boys of the same age in cat C. Lastly, he categorized pregnant women as cat D. He needs to recommend healthy diet, especially iron intake, for each group. Given the paragraph above, please answer correctly the following question: Which group would need more iron, cat B or cat C?

A: cat B

Problem: Helen is working in the kitchen when she goes to the freezer to get some ice cubes. There is only one ice cube left so she takes it out and sets it in the glass on the table. She then refills the ice cube tray with water and sticks it back in the freezer. Given the paragraph above, please answer correctly the following question: Is the density of the ice cube increasing or decreasing?

A: decreasing

Problem: Mary had two children. Her firs born was named Bill and was normal, and her second child was named Sam and had Down syndrome. Given the paragraph above, please answer correctly the following question: Which child didn't have an autosomal trisomy ?

A: Bill

Problem: Frank and Noah were two researchers. Noah researched the climate of Antarctica, while Frank researched the climate changes of Madagascar and the Southern tip of Africa. Given the paragraph above, please answer correctly the following question: Which researcher didn't observe a stronger warming in spring?

A:
Frank