Select the correct statement. ""Brother"" and ""male sibling"" are not synonymous. It cannot be known a priori that a brother is a male sibling. ""A brother is a brother"" is a non-trivial statement. ""A brother is a brother"" and ""A brother is a male sibling"" differ in cognitive value. ""A brother is a brother"" and ""A brother is a male sibling"" don't differ in cognitive value.

The correct statement is the one that reads """A brother is a brother"" and ""A brother is a male sibling"" differ in cognitive value.". Cognitive value is thought as a collective pool of considerations; meanings are assigned according to different processes such as thinking, reasoning, or remembering. In this case, the two statements presented above differ in cognitive value because the speaker assigns different values to the same noun "brother". In the first statement, the speaker considers a brother just a brother (A brother is a brother) and in the next statement the speaker considers a brother a male sibling, giving the same noun "brother" another value (A brother is a male sibling). The rest of the options are wrong, since the concept "brother" and "male sibling" can be used synonymously (with a different value according to the speaker), we cannot be sure if the sentence is trivial or not because it depends on the speaker's intention, and the two statements do differ in cognitive value.