OE


C, E

The first sentence describes Eugenius Outerbridge, who is only remembered in the name of a bridge, and the second sentence says that he may yet be forgotten. The word in the blank describes Outerbridge in relation to the bridge; since it was named after him, a good prediction would be namesake. (C) titular means "something from which a title was taken." For example, the titular character of a book is one who appears in the book's title (as in Tess of the d'Urbervilles or Harry Potter and the Philosopher's Stone), so this is a good match for the prediction. (E) eponymous refers to "something from which a name is derived," so it's another match for the prediction.
(A) secluded and (F) cloistered both mean "hidden" or "isolated." These words might describe the bridge, but the blank relates to Outerbridge. (B) disparate means "distinct" or "different." There's nothing in this sentence to support this idea, so eliminate it. (D) manifold means "diverse" or "many," which also doesn't fit here.