OE
The sentence states that solider ants guard the colony and supply it with food, “thus acting as both _________ and laborers.” In this sentence pattern, the first blank matches up with “guard the colony” and “laborers” matches up with “supply it with food.” “Sentries,” or guards, matches perfectly and is the correct word for blank (i). A “sage” is a wise scholar and a “sycophant” is a lackey or flatterer, neither of which fits the meaning of the sentence. The sentence then states that the queen can continually “populate the colony,” so “fecund” (fertile) goes in blank (ii) and progeny (offspring) goes in blank (iii). “Efficacious” means effective and “imperius” means domineering, but the sentence does not indicate that this would describe the queen ant. “Forebears” means ancestors, which is the opposite of what blank (iii) requires.
Finally, “harbingers” means a herald or a forerunner of something else, but producing signs of something else would not help to populate a colony.
Answer: A,D,H