Select the most appropriate option to substitute the underlined segment in the given sentence: It can be considered a branch of either philosophy and education.

Correct option is A

The correct answer is (a) both. The use of “either” in the sentence is incorrect when followed by “and.” The correlative conjunction “either” must be paired with “or” (i.e., “either X or Y”). However, the sentence uses “and,” which suggests inclusion of both items, not a choice between them. Therefore, the correct pair to use is “both...and”, which aligns with the intended meaning.
Correct sentence: "It can be considered a branch of both philosophy and education."
This construction accurately conveys that the subject belongs simultaneously to both disciplines — philosophy and education.