What Is the Evidence That Human Activity Is Causing Increased

question 56

Multiple Choice

What is the evidence that human activity is causing increased atmospheric CO₂ levels?

• A)The isotopic composition of atmospheric CO₂ can be measured and shows that CO₂ being added to the air now comes from combustion of fossil fuels.
• B)There is a correlation between the increase of overall CO₂ levels and human activity since the Industrial Revolution.
• C)There is no direct evidence; CO₂ levels fluctuate naturally and it may just be coincidence that higher CO₂ levels correspond to this period of human activity.
• D)There is no direct evidence; it is impossible to know what CO₂ levels were like in the past, so there is no standard for comparison.
• E)Since forests are being cut down by humans, CO₂ levels must be rising because there are fewer plants that remove CO₂ through photosynthesis.

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Definitions:

Symbolic Functioning

The ability to use symbols, signs, or objects to represent something else, a milestone in cognitive development allowing for complex thought.

Concrete Operations

A stage in Piaget's theory of cognitive development, typically from ages 7 to 11, when children gain the ability to think logically about concrete events.

Sensorimotor Period

The first of Jean Piaget's four stages of cognitive development, ranging from birth to about 2 years old, where infants learn about the environment through sensory experiences and motor activities.

Egocentrism

The cognitive inability to differentiate between one's own perspective and that of others, often seen in early childhood.