Task: Question Answering
Input (English): For all positive values of \(p\) and \(q\), let \(p \circledast q\) be defined by \(\frac { pq } { p + q } \). If \(p \circledast q = \frac { 1 } { p } \circledast \frac { 1 } { q } \), which of the following must be true?
(A)\(p = q + 1\) (B)\(p = q\) (C)\(p = -q\) (D)\(pq = 1\) (E)\(pq = p + q\)
Output (English): D