1.Justin (write)_____his speech for the presentation now I hope he finishes it before we meet. a. is writing b.will write c.writes d. has been writing?

The answer to this has to be a) is writing. Otherwise, it does not make sense. "Justin is writing his speech for the presentation now, I hope he finishes it before we meet."

The word now is very significant as that puts it into the present tense. Therefore 'has been writing' does not make sense as that indicates that he has finished, which doesn't fit in with the word 'now'. If the sentence was "Justin has been writing his speech all afternoon" that would be correct.

Similarly 'will write' is talking about a time in the future - "I will write to my aunt tomorrow".

'Writes' is also incorrect in this scenario too, it would be better used in a sentence such as "Josh writes for a local newspaper".

Tenses are quite complicated generally, and some people struggle with them more than others. I have heard some very bad examples of tenses being misused which is forgivable when the person is not English, but not so much when they are :-)