Question

all other things being equal, the larger a wind turbine’s rotor diameter (the diameter of the imaginary circle swept by the turbine’s rotating blades), the greater amount of energy the turbine can generate. in a research paper on wind power, a student claims that in the united states, the amount of energy generated per newly installed turbine increased substantially between 2011 and 2021. which choice best describes data in the graph that support the student’s claim? choose 1 answer: a in 2011, nearly 80% of turbines installed had rotor diameters of less than 100 meters, whereas only a little more than 20% of turbines installed that year had rotor diameters of 100-115 meters. b no turbines installed in 2011 had rotor diameters greater than 115 meters, whereas the majority of turbines installed in 2021 had rotor diameters greater than 130 meters. c most turbines installed in 2011 had rotor diameters of less than 100 meters, whereas most turbines installed in 2021 had rotor diameters of at least 115 meters. d the percentage of newly installed turbines with rotor diameters greater than 130 meters increased every year between 2011 and 2021.

Explanation:

To support the claim that energy per turbine increased (larger rotor diameter means more energy), we need data showing a shift to larger diameters from 2011 to 2021.

• Option A: Only describes 2011, no 2021 comparison. Eliminate.
• Option B: "Majority" in 2021 with >130m is extreme; likely not accurate. Eliminate.
• Option C: In 2011, most <100m (small); in 2021, most ≥115m (larger). This shows a shift to larger diameters, supporting more energy.
• Option D: "Increased every year" is too strict; the claim is about substantial increase overall, not yearly. Eliminate.

Answer:

C. Most turbines installed in 2011 had rotor diameters of less than 100 meters, whereas most turbines installed in 2021 had rotor diameters of at least 115 meters.