Read the following passage and mark the letter A, B, C, or D to indicate the correct answer to each of the questions.

Standing on the banks of River Yamuna, the Taj Mahal is synonymous to love and romance. The name "Taj Mahal" was derived from the name of Shah Jahan's wife, Mumtaz Mahal, and means "Crown Palace". The purity of the white marble, precious stones and its perfect location, all make a visit to the Taj Mahal gain a place amongst the most desirable tours in the world. However, until you know the love story behind the construction of the Taj Mahal, the beauty of the place would not shine in your heart and mind and instead would become as just another beautiful building or monument. It is the love behind this outstanding monument that has given a life to it.

At the break of dawn when the first rays of the sun hit the roof of this monument, it seems to be covered with bright gold. And then at night, under the glory of moon, it shines like a perfect diamond, leaving the viewers impression by its unbelievable beauty. It stands proud at being one of the Seven Wonders of the World. And the rich beauty of this visual place melts people's hearts when one hears the story behind it. The story of Taj Mahal!

Many public transit users buy monthly bus passes (23) ___________ they are cheaper and more convenient.