Some parts of the sentences have errors and some are correct. Find out which part of 2 sentence has an error and blacken the oval corresponding to the appropriate leer (A), (B, (C). If a sentence is free from error, blacken the aval corresponding to (D) in the Answer Sheet.
`underset((A))("I have")// underset((B))("known him") // underset((C))("since two years"). underset((D))("No error")`

Answer

C