Telling the time/ answer to "que hora es"

Question

When you are telling time, how do you say the "o'clock" part? For example, if you were asked, "Que hora es," what would you respond'

Answer 1

En punto implies that it is exactly five o'clock. It is correct, but generally people just say:
Son las cinco.

Answer 2

Click on lessons at the top, there is one on telling time