The answer is France.
France established the first colony in the Pacific by claiming Tahiti in 1842. French missionaries had been active on the island since the late 1700s, and in 1842, France sent a warship to Tahiti to demand a French protectorate. The Tahitian queen, Pomare IV, was forced to agree, and Tahiti became a French colony in 1880.
The other answer choices are incorrect:
Italy never established a colony in the Pacific.
Austria never established a colony in the Pacific.
Germany established a colony in the Pacific in the late 1800s, but it was not the first.
I hope this helps!