The one that is the best way to find the correct answer for a sentence completion question on a reading test is : c. look at the main parts or the paragraph and infer the answer
The main parts is basically the core of the content. If you find it, it would be really likely that you could answer a question about it
hope this helps
Answer:
My guess would be: It has Literal and Symbolic meanings. It helps to communicate an abstract concept.
Listeners get to use their imagination from the sounds on the radio as exemplified by a program in the early '60's called he Goon Show of the BBC in London which was a comedy show with many sound effects like horses clopping which made the program very entertaining.
