From the words or group of words lettered A to D, choose the word or group of words that best completes each of the following sentences: By Christmas, I.......

Answer Details

The correct option is "shall have been working." This is because the sentence is referring to a future event (Christmas) and also implies that the person will have been working continuously for one year by that time. The future perfect tense is used in such a context. The option "shall have been working" is the correct usage of the future perfect tense. The other options are in different tenses and do not fit the context of the sentence.