Hint: Shah-I-Bekhabar was the seventh Mughal emperor of India who ruled from 1707 to 1712. He was the third son of Aurangzeb.
Complete answer: Bahadur Shah was also known as Shah-I-Bekhabar. This name was given by Khafi Khan because he liked to appease all parties by profuse grants of titles and rewards. He ruled for five years from 1707 to 1712. He was also the governor of Akbarabad, Kabul and Lahore from 1696 to 1707. When he was young, he conspired to overthrow his father and ascend to the throne a number of times but his plans were intercepted by the ruler, who then imprisoned him several times. His reign was disturbed by Sikh under the leadership of Banda Singh Bahadur, Rajputs and fellow Mughal Kam Baksh but slowly and gradually all of them were successfully suppressed.
Looking at the options given:
Option A. Bahadur Shah is the correct answer as he was popularly known as Shah-I-Bekhabar (the Heedless king), the name given by Khafi Khan.
Option B. Jahandar Shah was the son of Bahadur Shah. It is an incorrect option.
Option C. Muhammad Shah was also known as Sada Rangila or Muhammad Shah Ranglia. It is an incorrect option.
Option D. Shah Alam I, also known as Bahadur Shah. It is an incorrect option.
Hence, The correct answer is Option A.
Note: Bahadur Shah was popularly known by different names like Muhammad Muazzam, Shah Alam and Shah-I-Bekhabar. His habits and personality made him get these multiple names.