Structure and Written Expression 
1. Simple photographic lenses cannot ______sharp, undistorted images over a wide field. 
(A) to form 
(B) are formed 
(C) forming 
(D) form 
2. Of all the factors affecting agricultural yields, weather is the one ______ the most. 
(A) it influence farmers 
(B) that influences farmers 
(C) farmers that it influences 
(D) why farmers influence it 
3. Beverly Sills, ______, assumed directorship of the New York City Opera in 1979. 
(A) be a star soprano 
(B) was a star soprano 
(C) a star soprano and 
(D) a star soprano 
4. ______ of tissues is known as histology. 
(A) Studying scientific 
(B) The scientific study 
(C) To study scientifically 
(D) That is scientific studying