For current affairs questions, always connect the role/appointment with the personality's contribution in the same domain (sports, health, education, etc.).
Step 1: Understand the context.
The World Health Organization (WHO) appoints well-known personalities as Goodwill Ambassadors to promote public health awareness.
Step 2: Recall the fact.
Legendary Indian sprinter Milkha Singh, also known as the "Flying Sikh," was appointed as the WHO Goodwill Ambassador for physical activity in the South-East Asia Region (SEAR).
Step 3: Verify options.
- (a) Mary Kom → Famous Indian boxer, but not appointed in this role.
- (b) Milkha Singh → Correct; appointed as WHO Goodwill Ambassador (SEAR).
- (c) Pullela Gopichand → Badminton coach, not connected with this position.
- (d) Abhinav Bindra → Olympic gold medalist shooter, but not the appointee here. \[ \Rightarrow \boxed{\text{Milkha Singh is the correct answer.}} \]
Instead of recalling the appointment directly, this can be approached by matching each personality's sporting background to the role of promoting physical activity.
Only the sprinting legend fits the WHO's physical-activity ambassador role, pointing to option 2.
Hence, the correct answer is Milkha Singh.