The correct answer is: C. announced/had pulled.
The sentence is in the past tense, so the correct answer must be a verb in the past tense. Option A, had announced, is the past perfect tense, which is used to talk about something that happened before another event in the past. Option B, announces, is the present tense, which is not correct because the sentence is about something that happened in the past. Option D, is announcing, is the present progressive tense, which is not correct because the sentence is about something that happened in the past. Option E, has announced/was pulling, is not correct because the two verbs are in different tenses.
The sentence is about Russia pulling its troops out of Georgia. Option C, announced/had pulled, is the correct answer because it is a verb in the past tense that describes something that happened in the past.