A - Model-grade looks
To get to the point, I pick A. But the "bimbo" here must not be someone who is simply empty from the start — it should be someone who can change if she learns.
1) Looks work at the start, and intelligence lasts to the end
Because of her model-grade looks, A wins the other person's curiosity and attention easily at the first meeting. That starting point is not bad, while B starts from a disadvantaged position because of her looks. Conversely, conversation and learning grow more rewarding as time goes on.
2) Society can cover B's shortcoming, but A's cognitive gap is hard to cover
A devoted homemaker can change how people look at her, even with plain looks, through warmth, tidiness, tone of voice, and how others judge her. But if the other person cannot understand what you say, the conversation breaks off no matter how well she cooks. I see an A without intelligence as ahead of the homemaker.
3) Take the word "bimbo" literally and both choices lose
If A is truly someone who cannot learn, then B is the answer. But in reality she may just be clumsy at first and clumsy at expressing herself. I would give that person one more chance to learn and decide. Choose B, and you gain one more homemaker; choose A, and you may build a home much like B's.
Conclusion: I choose an A who can learn and talk, not B. Looks cannot stand in for all forty years.
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