詳解
文章第一點清楚寫著，持卡人可以 visit the city by metro, bus, or train as many times as you want。其中 as many times as you want 就是「想搭幾次就搭幾次」，也就是不限次數。
因此 (D) Move around the city by metro as much as you want 與原文意思相同。visit the city 換成 move around the city，as many times as you want 換成 as much as you want，都是同義改寫。
這題的重點不是複雜推論，而是精準核對三種常見資訊：折扣是多少、哪些項目不用付費、使用範圍到哪裡。應用文最容易錯在只看到某個關鍵字，卻沒有把它附近的數字和限制條件一起讀完。