Which of the following curves is a rectangular hyperbola?

Average fixed cost (AFC) is AFC= FC/Q, as production increases the value of Q increases and thus value of AFC will become smaller and smaller and get reaches near and near to X-axis but can never touch the X-axis because AFC can not become exact zero. Thus the AFC becomes the shape of rectangular hyperbola curve. It shows unitary elasticity because we know that the elasticity on points on rectangular hyperbola curve is equal to one.}