When Solomon discovered that his encounter with God was a dream, his response was:

A. offered burnt offering before the ark.

This incident is recorded in the Bible, specifically in 1 Kings 3:15. After Solomon's dream in which God offered him anything he desired, Solomon woke up and realized it was a dream. He then went to Jerusalem and stood before the Ark of the Covenant, offered burnt offerings, and prepared a feast for all his servants. This indicates his reverence for the dream and his commitment to fulfilling what God had spoken to him in the dream.