The Prime Minister ___________ that the country could only _______ economically if planners had a clear _______ of rural development in the context of growing unemployment.

The Prime Minister believed that the country could only progress economically if planners had a clear concept of rural development in the context of growing unemployment. For the first blank, 3^rd person present form of verb BELIEVES or past participle form BELIEVED/THOUGHT can be used. For the second blank, POGRESS is the correct usage as DEVELOPS is the incorrect form. (DEVELOP would have been correct. Verb with could does not change its form according to the subject). With BELIEVED and PROGRESS, CONCEPT is given and it is appropriate for the 3^rd blank.