Since the child lived with you more than half the time since birth, she qualifies as a dependent. Because of how Turbotax asks the question, answer "all year" (or anything longer than 7 months) to get her qualified.
Also, she must have been placed by an authorized agency under state law. Some private placements may not qualify.
Also also, she needs a social security number. If you don't have it but it is applied for, don't file until you get it. Get an extension until October 15 if you need to. Certain tax credits will only be paid if the child has a valid SSN when you file an "on time" tax return. If you can't get an SSN because of the situation, but you are planning to adopt, you can apply for a temporary adoption tax number.
https://www.irs.gov/individuals/international-taxpayers/taxpayer-identification-numbers-tin
