In his arguments in Brown v. Board of Education, the lawyer for Oliver and Linda Brown claimed that "separate but equal" public schools were

separate but not truly equal.

Explanation:

According to a different source, these are the options that come with this question:

neither separate nor equal. separate but not truly equal. equal but not truly separate. both separate and equal.

In Brown v. Board of Education of Topeka, the lawyer for Oliver and Linda Brown argued that the doctrine of "separate of equal" did not operate in practice, as segregated schools could not be considered to be truly equal. The final ruling of the Court stated that, whether segregated schools were equal or not, they were unconstitutional. The Court stated that these violated the Equal Protection Clause of the Fourteenth Amendment of the U. S. Constitution.