Worked explanations
The paper carries one for every question, at the back. These are the three above.
Q1
D
Ch. 1: English Language Skills
Answer: D - The mold was found behind the paneling in the second-floor classroom.
Because A sentence needs a subject and a finite verb and must not be left dependent. "The mold was found" supplies both and stands alone. Competencies s.82 ELS 1.3
Where the other options lead
- A.Participial phrase with no subject. Nothing says what was found, so the group of words is a fragment.
- B.Noun phrase with no verb. There is a subject but no predicate, so nothing is asserted.
- C.Relative clause standing alone. "Which" makes the clause dependent on a noun that never appears.
Q2
D
Ch. 2: Reading
Answer: D - Volunteers are concentrated near towns and roads
Because Where nobody is watching, nothing is recorded, so the distribution of records partly reflects the distribution of watchers.
Where the other options lead
- A.Names a different distortion. That is the effort problem; the map problem is where observers are.
- B.Names the skill problem. Skill affects the reliability of a record, not the geography of the map.
- C.Substitutes a real ecological difference. The passage is describing a distortion introduced by the observers, not a true pattern.
Q3
B
Ch. 2: Reading
Answer: B - By recording effort and estimating detection probabilities
Because It adds that analyses estimate a detection probability for each observer and each condition.
Where the other options lead
- A.Invents a simple correction. The correction described is a model of detection, not a flat regional weighting.
- C.Substitutes exclusion for modeling. The passage says the distortions are modeled rather than wished away.
- D.Introduces a validation survey. The passage says no professional survey could cover the same ground.