Why does the filmmaker decide to make a documentary about Kamkwamba’s story?

A Kamkwamba is a hero who improved living conditions in his country.
B He is interested in windmills and how they work.
C He has learned about Kamkwamba’s story and wants it to reach a wider audience.
D He wants to expose the terrible living conditions in Malawi before the windmill was built.

C). He has learned about Kamkwamba’s story and wants it to reach a wider audience.

Explanation:

The filmmaker decided and was determined to frame a documentary relating to Kamkwamba's story as he 'learned about his story of rising from a state of relative poverty to innovating the 'wind turbine' that produced electricity'. His striving and engrossing tale to accomplish his dreams would encourage the majority to initiate their steps towards their dreams and hence, would be able 'to relate to a wider audience'.

the answer is "began" because it is a action that can be done

that is based on your opinion not an answer someone can just give you unless you want to lie on your opinion. no offense wasn't trying to be rude. tip: use words like instead of don't put do not and you get what i mean