Question

as the work continued, 37 therefore, the team faced obstacles. fieldwork in a city has to be done intermittently: the construction crew had to proceed one block at a time to avoid interrupting traffic, and the archaeology team’s work was periodically 38 halted—by stormy weather and the discovery of toxic materials underground. moreover, as archaeologists underground attempted to relay information to those at the surface, they had to contend with the noise of construction vehicles, car horns, and 39 pedestrians’ noise on the busy new york city streets.
37
a) no change
b) though,
c) meanwhile,
d) similarly
38
a) no change
b) halted;
c) halted,
d) halted
39
a) no change
b) the noise of pedestrians
c) pedestrians
d) that of pedestrians

Explanation:

Question 37

The original "therefore" implies a causal relationship, but the context shows a contrast (work continued yet obstacles were faced). "though" (B) introduces contrast, fitting better. "meanwhile" (C) is for time - parallel actions, "similarly" (D) for similarity, neither fits. So B is correct.

The sentence uses an em - dash to introduce explanations for why the work was halted. The original "halted—" (A) is correct. A semicolon (B) would need a separate independent clause, a comma (C) would make it a run - on, and removing the em - dash (D) loses the explanatory structure. So A is correct.

The list is "construction vehicles, car horns, and...". To maintain parallelism, we need a noun phrase like the others. "the noise of pedestrians" (B) is parallel to "construction vehicles" (noun), "car horns" (noun). "pedestrians' noise" (A) is possessive, "pedestrians" (C) is just a noun (not noise), "that of pedestrians" (D) is awkward. So B is correct.

Answer:

B) though.

Question 38