Differentiate between the sentences: ‘I read a book’ and ‘I am reading a book.’

A. ‘I read a book’ refers to a past action, while ‘I am reading a book’ refers to a present ongoing action.

B. ‘I read a book’ is a question, while ‘I am reading a book’ is a statement.

C. ‘I read a book’ indicates a habitual action, while ‘I am reading a book’ indicates a completed action.

D. ‘I read a book’ refers to a future action, while ‘I am reading a book’ refers to a past action.