Instruction: Identify the assumptions that must hold for the statement to be valid, then choose the correct option. Statement: Deforestation in tropical rainforests, primarily driven by agricultural expansion and logging, not only contributes to the loss of biodiversity but also exacerbates global warming by reducing the Earth's capacity to absorb carbon dioxide. Assumptions: I. Deforestation reduces the Earth's ability to absorb carbon dioxide. II. Agricultural expansion and logging are the primary causes of deforestation. III. The loss of biodiversity is the most significant consequence of deforestation.

Correct — A.
Rule: keep what the statement depends on; drop what it does not need.

I: the statement says deforestation worsens warming by reducing the Earth's capacity to absorb carbon dioxide. If I were false, that claim fails. Needed.

II: the statement calls deforestation primarily driven by agricultural expansion and logging. Needed.

III: nothing in the statement ranks the effects. Not needed.

I and II → option (a).

Why the others are wrong

• (b)
  Only II and III are implicit — It adds III, which the statement never claims: nothing calls biodiversity loss the most significant consequence. It also leaves out I, on which the warming claim rests.
• (c)
  Only I is implicit — It leaves out II, yet the statement itself names agricultural expansion and logging as the primary drivers, so II must hold too.
• (d)
  All I, II and III are implicit — It adds III, a ranking. 'Not only … but also' sets the two effects side by side, so the statement stands whether or not III is true.

A statement–assumption item asks what must already be true for the statement to make sense. Test each assumption by negating it: if the statement collapses, the assumption is needed.

Negate I and the warming mechanism disappears. Negate II and 'primarily driven by agricultural expansion and logging' becomes false. Negate III and nothing in the statement changes, because the statement ranks nothing.

Key facts

• Negation test: deny the assumption and see whether the statement still stands.
• 'Not only … but also' adds a second point without ranking the two.
• III brings in a claim, 'most significant', that the statement never makes.

Common traps

• Accepting III because biodiversity loss is mentioned first
• Rejecting I and II because the statement states them outright, when the instruction asks what must hold for it to be valid

No directly related past PYQ was found.