Explanation
Correct answer: B.
Choice B is the best answer. “For example” logically signals that the information in this sentence—that tadpole shrimp embryos can pause development during extended periods of drought—exemplifies the previous sentence’s claim that organisms have evolved surprising adaptations to survive in adverse conditions.
Why the other choices are wrong
Choice A
Choice A is incorrect because “in contrast” illogically signals that the information in this sentence contrasts with the claim about organisms in the previous sentence. Instead, it exemplifies this claim.
Choice C
Choice C is incorrect because “meanwhile” illogically signals that the information in this sentence is separate from (while occurring simultaneously with) the claim about organisms in the previous sentence. Instead, it exemplifies this claim.
Choice D
Choice D is incorrect because “consequently” illogically signals that the information in this sentence is a consequence, or result, of the claim about organisms in the previous sentence. Instead, it exemplifies this claim.