Final answer:
In a disparate-impact case, the burden on the plaintiff is to prove that the defendant's claim of business necessity is a pretext for discrimination.
Step-by-step explanation:
In a disparate-impact case, if a defendant can avoid liability by demonstrating that the discrimination was a business necessity, the burden on the plaintiff is to prove that the necessity is a mere pretext for discrimination. This means that the plaintiff needs to show that the defendant's claim of business necessity is not genuine and is just a cover-up for discriminatory practices. They must present evidence that the defendant's actions were motivated by discriminatory intent rather than a legitimate, nondiscriminatory business reason.