Before feeding the five thousand in John 6, which disciple did Jesus test by asking where to buy bread?

Answer: Philip

Jesus asked Philip to test him. Philip said two hundred denarii would not buy enough for each to have a little.

“When Jesus looked up and saw a large crowd coming toward Him, He said to Philip, “Where can we buy bread for these people to eat?” But He was asking this to test him, for He knew what He was about to do. Philip answered, “Two hundred denarii would not buy enough bread for each of them to have a small piece.””— John 6:5-7 (BSB)