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> In Ayrshire cattle, the mahogany/red locus is an autosomal gene. In both sexes, mahogany homozygotes are mahogany colored, and red homozygotes are red. However, the mahogany/red heterozygote is mahogany if male and red if female. Here is a pedigree for an Ayrshire family that is of great interest to Farmer MacDonald. (In the pedigree, open circles and squares indicate the mahogany phenotype; filled indicate red.) Although Elmer has long ago become a huge pile of Big Macs, Farmer MacDonald has frozen a good supply of Elmer's semen and has used it to artificially inseminate Elmira. What is the probability that Elmira will produce a mahogany female calf?
A. 1/2
B. 1/4
C. 3/4
D. 1/8
E. 1/16

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
E
<image 1> In Ayrshire cattle, the mahogany/red locus is an autosomal gene. In both sexes, mahogany homozygotes are mahogany colored, and red homozygotes are red. However, the mahogany/red heterozygote is mahogany if male and red if female. Here is a pedigree for an Ayrshire family that is of great interest to Farmer MacDonald. (In the pedigree, open circles and squares indicate the mahogany phenotype; filled indicate red.) Although Elmer has long ago become a huge pile of Big Macs, Farmer MacDonald has frozen a good supply of Elmer's semen and has used it to artificially inseminate Elmira. What is the probability that Elmira will produce a mahogany female calf?
A. 1/2
B. 1/4
C. 3/4
D. 1/8
E. 1/16

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