In the following questions, four words in the sentence

Solution

The phrase “catalytic role” is appropriately used to describe how public capital expenditure stimulates activity. The word “crowding” is acceptable as a gerund functioning within the phrase “role in crowding growth impulses,” which implies stimulating or triggering growth across sectors. Although “crowding in” is more commonly used, the absence of “in” does not make the sentence incorrect in this context. Each highlighted word fits logically and grammatically where it is placed. Any attempted interchange would either distort meaning or introduce grammatical inconsistency. Hence, no interchange is required, making option (e) correct.