For which of the following reasons is the recognition as an asset of an internally generated intangible

Question:

For which of the following reasons is the recognition as an asset of an internally generated intangible prohibited?
(a) Because there may not be an active market for that asset
(b) Because its cost is usually relatively insignificant
(c) Because it is difficult to reliably identify the related costs
(d) Because it is difficult to establish the probability of flow of economic benefits