You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Westminster_Abbey

Context:
A recent addition to the exhibition is the late 13th-century Westminster Retable, England's oldest altarpiece, which was most probably designed for the high altar of the abbey. Although it has been damaged in past centuries, the panel has been expertly cleaned and conserved.

Question:
What is the Westminster Retable?

England's oldest altarpiece