Civilization develop(A) a complex way of life(B) that

Solution

The plural/base verb 'develop' doesn't justify the singular subject 'civilization' according to the subject-verb agreement rule. 'Describes' is a singular verb. It fits perfectly in the first position. So, A and D should be interchanged. The base verb 'develop' fits perfectly in the fourth position as it follows the infinitive marker 'to' which requires a base verb after it. The word 'urban' (in, relating to, or characteristic of a town or city) is an adjective. It doesn't fit in the third position as there should be a noun as it follows the preposition 'as'. The word fits in the last position as the adjective qualifies the noun 'settlements'. Also, the noun 'people' becomes the subject of the verb 'began'. So, C and E should be interchanged. The noun 'people' fits perfectly in the third position. Hence, option (d) is the correct answer. The correct sentence is: Civilization describes a complex way of life that came about as people began to develop networks of urban settlements.