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:
Alps

Context:
The English word Alps derives from the Latin Alpes (through French). Maurus Servius Honoratus, an ancient commentator of Virgil, says in his commentary (A. X 13) that all high mountains are called Alpes by Celts. The term may be common to Italo-Celtic, because the Celtic languages have terms for high mountains derived from alp.

Question:
Who says that all high mountains are called Alpes by Celts?

Maurus Servius Honoratus