Explanation
Correct answer: A.
Choice A is the best answer. The convention being tested is the use of verbs to express tense. In this choice, the simple past tense verb “suggested” properly indicates that Zufall offered her suggestion for the product’s name in the past. This verb tense is consistent with the previous sentence’s use of a simple past tense verb (“advised”) to describe Zufall’s advice to McVicker in the 1950s.
Why the other choices are wrong
Choice B
Choice B is incorrect because the present tense verb “suggests” doesn’t indicate that Zufall offered her suggestion in the past.
Choice C
Choice C is incorrect because the past perfect verb “had suggested” isn’t consistent with the previous sentence’s use of the simple past tense verb “advised” to describe Zufall’s advice to McVicker.
Choice D
Choice D is incorrect because the past progressive verb “was suggesting” isn’t consistent with the previous sentence’s use of the simple past tense verb “advised” to describe Zufall’s advice to McVicker.