You closed in on the correct answer if you chose B. Both "close" and "secluded" have origins in the Latin word "claudere" which means "to close." Latin speakers used "claudere" to form the verb "secludere," meaning "to separate, seclude." In Middle English, "secludere" became the verb "seclude" which meant "to cut off (from)." Eventually English speakers started using "secluded," a form of "seclude," as an adjective. Other words which trace to "claudere" include "conclude," "exclude," "include," and "recluse."