The question says that manager’s strategy is “to add value by identifying undervalued securities and sectors to take advantage of bonds that are mispriced by the market”. Then we see that the manager had added 0.3% return from “Other management effects”.
How can you conclude that the manager’s statement is true? It seems to me that we cannot say if he added 0.3% by identifying undervalued securities as he says. He may have sold short overvalued securities or done e.g. call positioning. We would never know this by just looking at 0.3% added value.