The question given below consists of a statement, followed by three or four…

Concept: In statement-argument reasoning, a 'strong' argument is one that is directly relevant to the practical decision in the statement, addresses a substantial aspect of the issue, and rests on a real cause-effect link -- not a personal opinion, an exaggerated generalisation, or a fact that stays constant regardless of the decision. A 'weak' argument sounds plausible but fails one of these tests.

Application: The statement asks whether overqualified candidates should be barred from a job. Argument I claims barring them worsens unemployment -- but the total number of vacancies to be filled does not change with who fills them, so overall employment is unaffected either way. Argument II claims overqualification creates workplace complexes that hurt performance -- this is a personal assumption about behaviour, not an established cause-effect link. Argument IV claims allowing overqualified candidates raises productivity -- but a job's productivity requirement is already fixed by its stated qualifications, so extra qualification does not automatically add value. Argument III, however, appeals to a substantial and directly relevant principle: a candidate who meets the eligibility criteria has a right to be considered for the post, regardless of any extra merit they hold.

• I is weak: barring overqualified applicants does not change the fixed number of vacancies, so unemployment is not 'aggravated'.

• II is weak: the claim about complexes among employees is a generalised assumption, not a demonstrated effect.

• IV is weak: a post's productivity requirement is set by its own eligibility criteria, so extra qualification does not necessarily raise output.

• III is strong: it rests on the individual's basic right to seek any post they are eligible for, which is a substantial and directly relevant principle.

Since only the individual-rights argument survives this test, the correct choice is 'Only III is strong'.