If TP=9 FP=6 FN=26 TN=70 then Error rate will be

The correct answer is C. 28 percentage.

The error rate is the percentage of instances that are incorrectly classified. It is calculated by dividing the number of errors by the total number of instances, and multiplying by 100. In this case, there are 9 true positives, 6 false positives, 26 false negatives, and 70 true negatives. The error rate is therefore:

$Error\ rate = \frac{6 + 26}{9 + 6 + 26 + 70} \times 100 = 28\%$

Option A is incorrect because it is the percentage of false positives. Option B is incorrect because it is the percentage of false negatives. Option D is incorrect because it is the percentage of true negatives.