This is an edit from my previous answer.
Initially I wrote that there were 5 collinear points. My line of reasoning was that A,B,C are on one line (making them collinear), and points D,B,E are on another line (another set of collinear points).
However, if the question is asking how many collinear points are on one particular line, then the answer would be 3 collinear points. You can focus on either line and it's the same number of collinear points.
Definition: The term "collinear" means all points fall on the same straight line.
