Answer:
a) The depiction of pathos and emotion in a composition constructed with sweeping curves.
This is the oldest work that with some extent of certainty could also be attributed to Rogier van der Weyden; the master never signed his work. If this is often the case, it's in all probability additionally his most spectacular work. As a screen it had been meant for a chapel in Leuven, however, fell into Spanish hands within the sixteenth century. Today, it's on show in the Prado in the Spanish capital.