Two observers are stationed due north of a tower (of height x meter) at a distance y meter from each other. The angles of elevation of the tower observed by them are 30° and 45° respectively. Then x/y is equal to

• A. (√2 – 1) /2
• B. (√3 – 1) /2
• C. (√3 + 1) /2
• D. 1