Explanation
Correct answer: B.
Choice B is the best answer. "Indeed" logically signals that the information in this sentence—that the sculpture raised the question of whether displaying any object in an art gallery transforms the object into a work of art—offers emphasis in support of the claim in the previous sentence that the sculpture was intended to challenge conceptions about the nature of art.
Why the other choices are wrong
Choice A
Choice A is incorrect because "similarly" illogically signals that information in this sentence is similar to the claim about the sculptor’s intention in the previous sentence. Instead, the information about the question raised by the sculpture offers emphasis in support of that claim.
Choice C
Choice C is incorrect because "instead" illogically signals that the information in this sentence is an alternative to the claim about the sculptor’s intention in the previous sentence. Rather, the information about the question raised by the sculpture offers emphasis in support of that claim.
Choice D
Choice D is incorrect because "in addition" illogically signals that the information in this sentence is merely an additional fact related to the claim about the sculptor’s intention in the previous sentence. Instead, the information about the question raised by the sculpture offers emphasis in support of that claim.