One of the oldest, best preserved and most complete hominid fossil commonly known as ‘Lucy’ belongs to the genus

Question

$\begin{array}{1 1} \text{a. Australopithecus} \\ \text{b. Oreopithecus} \\ \text{c. Dryopithecus} \\ \text{d. Pithecanthropus } \end{array} $