Explanation:When two lines are perpendicular, the slope of one is the negative reciprocal of the other.The given equation:

x= y

or y = 1.x (where slope = 1)

The line to be perpendicular the slope needs to be negative reciprocal i.e. Slope(m) = \(\frac{1}{{-1}}\).

option C can be written as :\(y = -x\) or \(y = \frac{1}{{-1}} * x\), where the slope is negative reciprocal

Option D can be written as : \(x + y = 1\) or \(y = -x - 1\)or \(y = \frac{1}{{-1}} *x - 1\), where the slope is negative reciprocal

Rest of the options don't satisfy the rule and hence are out.

Option C and Option D are the answers
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