US, Indonesia and Australia holds drill in Sumatra islands

Current Context: US, Indonesia, and Australia joined live-fire drills, part of an annual joint combat exercise in the Sumatra Islands.

• This year's Super Garuda Shield Exercises was participated by more than 5,000 personnel from the US, Australia, Japan, Indonesia, and Singapore, making it the largest since it began in 2009.
• China sees the expanded drill as a threat and has accused the US of building an Indo-Pacific alliance similar to NATO to restrict China's growing military and diplomatic influence in the region.
• India, Canada, France, the United Kingdom, Malaysia, South Korea, New Zealand, Papua New Guinea, and East Timor has sent observers to the exercise.
• The 14 nations involved in the exercise are showing their strong ties as China grows increasingly assertive in claiming the entire South China sea and conducts exercises to threaten self-ruled Taiwan.

Question:

Q.1 US, Indonesia, and _______ joints live fire drill part of annual joint combat exercise in Sumatra Islands.
a. UK
b. Germany
c. Thailand
d. Australia