OG9 阅读 Q31

Choice B is the best answer. Figure 1 shows that guppies from low-predation environments (represented on the graph by second and fourth bars from the left) had smaller litters, or fewer guppy offspring, than did guppies from high-predation environments (represented by the first and third bars from the left). Similarly, figure 2 shows that guppies from low-predation environments (the second and fourth bars from the left) also had embryos with a greater mean mass than did guppies from high-predation environments (the first and third bars from the left).
Choice A is incorrect. Although figure 1 does support the conclusion that guppies from low-predation environments have fewer offspring than those from high-predation environments, neither figure indicates the time required for guppies to reach full maturity. Choice C is incorrect because neither figure indicates the survival rate of guppies, and figure 2 directly contradicts the conclusion that guppies from low-predation environments have less mean embryo mass than those from high-predation environments. Choice D is incorrect. Although figure 2 supports the conclusion that guppies from low-predation environments have a greater mean embryo mass than those from high-predation environments, figure 1 directly contradicts the conclusion that guppies from low-predation environments produce a greater number of offspring than those from high-predation environments.