Step 1: Understanding the Question:
The question asks to identify the Prime Minister with the shortest term in office among the given options.
Step 2: Detailed Explanation:
Let's examine the tenures of the Prime Ministers listed:
- (A) Morarji Desai: Served from 24 March 1977 to 28 July 1979 (2 years, 126 days).
- (B) Chaudhary Charan Singh: Served from 28 July 1979 to 14 January 1980 (170 days).
- (C) Chandra Shekhar: Served from 10 November 1990 to 21 June 1991 (223 days).
- (D) Gulzarilal Nanda: Served as the acting Prime Minister on two occasions, each for a very short period:
- First tenure: 27 May 1964 to 9 June 1964 (13 days) after Jawaharlal Nehru's death.
- Second tenure: 11 January 1966 to 24 January 1966 (13 days) after Lal Bahadur Shastri's death.
Even though he was an acting PM, his tenure was the shortest. If we consider non-acting PMs, Atal Bihari Vajpayee's first term in 1996 for 13 days would be the shortest, but he is not an option. Among the given choices, Gulzarilal Nanda's term of 13 days is the shortest.
Step 3: Final Answer
Among the given options, Gulzarilal Nanda had the shortest tenure as Prime Minister.