When a statement is implicit, it is actually suggested or implied but not clearly stated. It is usually understood but assumptions are often used.
From the passage, it was stated that when he look at his time, he discovered his watch was still on Eastern time. The passage didn't clearly state that he is from the Eastern Time Zone. It only suggested and implied that the man came from Eastern Time Zone.
Therefore, the correct answer is Martin has come from the eastern time zone because it was actually one's suggestion.
