Instruction: Identify the assumptions that must hold for the statement to be…

Concept

An assumption is an unstated proposition that the speaker must already be taking for granted for the statement to hold. The standard test is negation: deny the candidate proposition, and if the statement then loses its basis or stops making sense, that proposition is implicit. Two kinds of proposition never qualify — one that contradicts what the statement explicitly asserts, and one that pushes a stated fact into a stronger or more absolute claim than the statement itself commits to.

Applying the negation test here

The statement has two parts: a concessive clause conceding that recent advancements have significantly improved processing speeds, and a main clause asserting that the stability of quantum states remains a critical barrier to developing large-scale quantum computers for practical applications. Each candidate proposition is tested against those two parts.

• I — Quantum computing holds the potential for faster data processing than classical computing. The statement opens with a concession — that processing speeds have significantly improved — and sets it against the barrier it goes on to name. A concession only does its work if what is conceded is genuinely a point in favour, and a gain in processing speed counts in favour of quantum computing only when it is measured against the classical computing that quantum computing is meant to outperform. Negate the proposition and say that quantum computing has no speed potential beyond classical computing: the opening clause then concedes nothing at all, and the contrast on which the whole sentence is built collapses. So this proposition is being taken for granted.

• II — Quantum states are inherently unstable, making large-scale quantum computing unfeasible. The statement calls stability a critical barrier, that is, an obstacle development still has to get past. This proposition converts that obstacle into an intrinsic property and adds an absolute verdict, unfeasible. Negate it, and say instead that large-scale quantum computing is very hard today but not impossible: the statement survives untouched, and its own phrase about developing large-scale quantum computers for practical applications in fact describes work still under way rather than an abandoned goal. Since the statement stands without it, it is a stronger claim of its own, not something the statement takes for granted.

• III — Recent advancements have resolved the issue of quantum state stability. The statement says stability remains a critical barrier, which asserts the opposite. Because this proposition contradicts the explicit text, it fails the test outright and is not an assumption of the statement.

Cross-check

• Any selection that carries III sits directly against the word remains in the statement, so it cannot describe what the speaker presupposes.

• A selection that pairs I with II carries over the absolute word unfeasible, which the statement never commits to; calling something a barrier is weaker than calling the goal beyond reach.

Only one proposition survives the necessity test that the instruction demands, so the correct choice is “Only I is implicit”.