The correct answer to this question is 4.The map helps the reader understand Kalhat's location on the Gulf of Kalhat.
None of the paragraphs explaining about Kalhat talk about the elevation nor its size, so we can leave out options 1 and 3.
For option 2, the passage in question does not state anything about Sharkh, so therefore we can ignore this option as well, which leaves us with option 4 as the remaining and correct one. Also knowing that the passage in question talks about the location of the city within the gulf.