Mathematicians have long struggled with the problem of having non-Euclidian geometric concepts to represent on a two-dimensional surface.
(A) having non-Euclidian geometric concepts to represent on a two-dimensional surface
The problem was to represent, not having certain concepts. This choice illogically suggest that math doesn’t have non-Euclidian geometric concepts. It does.
(B) having a two-dimensional surface on which to represent non-Euclidian geometric concepts
The problem was to represent, not having certain concepts. This choice illogically suggest that math doesn’t have a two-dimensional surface. It does.
(C) how can one represent non-Euclidian geometric concepts on a two-dimensional surface
“how can one” is the structure of a question. A helping verb can precede the subject in questions, and this choice isn’t question.
(D) how they could use a two-dimensional surface to represent non-Euclidian geometric concepts
“they” doesn’t have an antecedent. It all the way around: to represent non-Euclidian geometric concepts on a two-dimensional surface
(E) how to represent non-Euclidian geometric concepts on a two-dimensional surface
Correct choice: the problem was the action of representing certain concepts on a two-dimensional surface.
Hence E