Explanation
Correct answer: B.
Choice B is the best answer. The claim is that some concentrations of H₂S led to increased germination rates, and this choice accurately shows that seeds treated with 10 micromoles per liter of H₂S tended to germinate faster than untreated seeds.
Why the other choices are wrong
Choice A
Choice A is incorrect. This choice doesn't justify the claim. The claim compares the germination rates of seeds exposed to certain concentrations of H₂S to untreated seeds, but this choice only discusses one concentration of H₂S, so it can't support any comparison between treated and untreated groups.
Choice C
Choice C is incorrect. This choice misreads the graph. At 168 hours, only about 85% of seeds treated with H₂S at 500 micromoles per liter and well over 70% of untreated seeds had germinated (about 80%).
Choice D
Choice D is incorrect. This choice misreads the graph. At 48 hours, about 70% of seeds treated with H₂S at 10 micromoles per liter and about 50% of untreated seeds had germinated.