Definition: In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.
Input: Question: During what years was the sprigs of eastern white pine worn as badges in Vermont? Passage:In the United States it is the State Tree of Maine (as of 1945) and Michigan (as of 1955). Its "pine cone and tassel" is also the State Flower of Maine. Sprigs of eastern white pine were worn as badges as a symbol of Vermont identity during the Vermont Republic and are depicted in a stained glass window in the Vermont State House, on the Flag of Vermont, and on the naval ensign of the Commonwealth of Massachusetts and the state of Maine. The 1901 Maine Flag prominently featured the tree during its brief tenure as Maine's state flag. The Maine State Guard also use the tree in their uniform badges.
Links: a. Flag of Maine (190109) b. Flag of Vermont c. Massachusetts d. Vermont Republic
Output:
d