Question

text 1
during a winter covid surge, the springfield, massachusetts, school
committee debated spending esser funds on co2 monitors. a
member argued that posting readings in each classroom would make
ventilation visible: when numbers climb above 1,200 ppm, teachers
can crack windows or move activities outside. she said co2 is a real-
time proxy for how much shared air students are breathing, so it
indicates when transmission risk is rising.

text 2
industrial hygienist luis ortega agrees monitors can prompt action,
but he notes co2 rises whenever many people are present, even if air
is clean and filtered. a high reading signals crowding plus limited
fresh - air exchange, not the presence of a virus. ortega recommends
pairing monitors with clear occupancy guidelines and periodic checks
of hvac airflow so staff respond to the right cause.

7 mark for review
based on the texts, how would the author of text 2 most likely
characterize the underlined statement in text 1?
a that co₂ readings reliably track shared air and also
verify whether a pathogen is circulating in the room.

b it is misleading because co₂ levels are unrelated to how
much fresh air a room receives, so monitors would not
guide ventilation decisions.

c it is accurate only when a room has no filtration, since
filtration cannot change co₂ levels and therefore makes
monitors pointless.

d it is mostly accurate; co₂ readings can reflect the buildup
of rebreathed air, but they cannot confirm that an
infectious agent is present.

Explanation:

To solve this, we analyze the underlined statement in Text 1 and Text 2:

• Text 1's statement: CO₂ is a real - time proxy for shared air (so transmission risk).
• Text 2: Luis Ortega says CO₂ rises with crowding (so re - breathed air buildup, as shared air would have re - breathed air) but can't confirm a virus (infectious agent) is present.
• Option A: Text 2 says CO₂ doesn't verify pathogen circulation, so A is wrong.
• Option B: Text 2 says monitors can prompt action (so they do guide ventilation decisions), B is wrong.
• Option C: Text 2 doesn't say monitors are pointless with filtration, just that high CO₂ with filtration is about crowding, C is wrong.
• Option D: Matches Text 2's view: CO₂ reflects re - breathed air (shared air) buildup (mostly accurate part) but can't confirm infectious agent presence.

Answer:

D. It is mostly accurate; CO₂ readings can reflect the buildup of rebreathed air, but they cannot confirm that an infectious agent is present.