Final answer:
Option B does not support the idea that Alfred was born great, as he was not expected to be king despite being the fourth of five sons.
Step-by-step explanation:
The pair of details that does NOT support the idea that Alfred was born great is option B. He was the fourth of five sons and was not expected to be king.
The other options all provide evidence that supports the idea that Alfred was born great. Option A mentions that he was a skilled warrior and strategist, while also being wise and learned. Option C states that he was born into a royal family and was raised to be a king. Option D, although similar to option B, specifies that he was the youngest of five sons and not expected to be king.