The correct answer is option (ii) mode. According to the textbook context, a histogram is a set of rectangles where the height represents the frequency (or frequency density) of class intervals. The tallest rectangle in a histogram represents the class with the highest frequency, which is the modal class. This allows for the graphical determination of mode. The mean cannot be found directly from a histogram as it requires actual values for calculation. The median requires cumulative frequency distribution and is best found graphically using an ogive, not a histogram. Therefore, among the given options, only the mode can be determined graphically from a histogram.