Accuracy: refers to the deviation of a measurement from a standard or true value of the quantity being measured.
Correctness: The degree to which a system is free from [defects] in its specification, design, and implementation.
Robustness: The degree to which a system continues to function(tolarates) in the presence of invalid inputs or stressful environmental conditions(Unexpected problems).
Reliability: The ability of a system to perform its requested functions under stated conditions whenever required - having a long mean time between failures.
So D. Robustness is Ans