Passage Summary: A school tried a new way of teaching plumbing, but since their students' pass rates are now lower than the national average, the school claims the new way is a failure.

Conclusion: The experimental curriculum at the Technology Institute has caused a decline in the quality of plumbing instruction.

Reasoning: Only one-third of the graduates passed the certification test, which is significantly lower than the national average.

Analysis: This argument makes a major leap by comparing the school's current pass rate to a national average without providing a baseline for the school's *previous* performance. We don't know if the pass rate was 50% or 10% before the change; if it was 10%, the new curriculum actually improved things! Additionally, the argument assumes the curriculum is the cause of the low scores without considering other factors, like the quality of the students or the difficulty of the test. Look for an answer that identifies this lack of a 'before and after' comparison. Just because the plumbers are struggling doesn't mean the new books are the leak in the system.