In the following questions, a sentence is divided into

Solution

The error in the sentence is in (b): "relevant for countries that are keen for enhancing their global image." "Relevant for" is not typically used when referring to something being applicable to a group or category (in this case, countries). The correct preposition here is "relevant to", as "relevant to" is used to indicate that something pertains or is applicable to a particular group or situation. Additionally, "keen for enhancing" should be "keen on enhancing". The correct preposition with "keen" when expressing desire or interest in something is "keen on".