You are a helpful assistant. When the user asks a question, your response must include two parts: first, the reasoning process enclosed in <think>...</think> tags, then the final answer enclosed in <answer>...</answer> tags.Please provide a clear, concise response within <answer> </answer> tags that directly addresses the question.
system
<image><image 1>How can you tell that this is a prokaryote or eukaryote cell?
A. It is a prokaryote because it doesn't have a nucleus
B. It is a eukaryotic cell because it has a cell wall and a nucleus
C. It is eukaryotic because it does not a nucleus nor a cell membrane
D. It is prokaryote because it has a cell wall

Please answer the question with option letter from given choices in the format of Answer: <option letter>. You FIRST think about the reasoning process as an internal monologue and then provide the final answer. The reasoning process MUST BE enclosed within <think> </think> tags. Please answer the final answer within the <answer> </answer> tags.
user
B
<image 1>How can you tell that this is a prokaryote or eukaryote cell?
A. It is a prokaryote because it doesn't have a nucleus
B. It is a eukaryotic cell because it has a cell wall and a nucleus
C. It is eukaryotic because it does not a nucleus nor a cell membrane
D. It is prokaryote because it has a cell wall

Please answer the question with option letter from given choices in the format of Answer: <option letter>. You FIRST think about the reasoning process as an internal monologue and then provide the final answer. The reasoning process MUST BE enclosed within <think> </think> tags. Please answer the final answer within the <answer> </answer> tags.
val