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If r = -1, the correlation is
AZero correlation
BPerfect negative
CWeak negative
DPerfect positive
Answer & Solution
Correct answer: B. Perfect negative
1. r ranges over [-1, +1] for linear correlation.
2. r = -1 implies all points lie on a line with negative slope.
3. This is called perfect negative correlation.
4. So the answer is 'perfect negative'.
_Source: ICAI BoS Foundation Paper 3, Ch 17 'Correlation', p.5_
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