Hi OP, I can't understand why you think that combination could possibly be unreasonable in any shape or form?
Can I ask - what is is you think she should be doing?
Unless she is one of those who has a burning mission to be a doctor, or teacher etc from a young age, it's absolutely normal to not be pinning yourself to a certain 'career' at 15/16. I would argue it's definitely preferable and far more realistic to have your options open at that age.
My DD did Geography, Economics and Spanish. She is now at Oxford studying Geography. It's a very relevant degree that lends itself to many careers (sustainability, global warming, global inequality - all big questions for this generation!) and she has been offered many internships (including ones in banks, international development agencies and even Amazon).
So with those A-levels, your DD could apply for Geography, Politics or English degrees (obviously). If she got top grades she would be perfectly placed to apply for HSPS (Human, Social, Political Sciences) at Cambridge. She could apply for Liberal Arts degrees anywhere. She could apply to Politics or Dual BA programmes at international institutions such as LSE or UCL. Or Anthropology degrees there - even Sociology-type degrees at those two unis, or the LSE degree Culture and Society. A degree from any of these top unis will open doors for her and give her so many options. Then, if she wants to specialise in a more career-specific area, she can do an MBA or a more specialist Masters programme.
These are brilliant A-levels which complement each other and will stand her in good stead. My only word of warning would be that if she wanted to apply for more Physical Geography courses (or Environmental Science or Geology), a Biology or Maths A-level may help for applications to unis offering purely those type of science- based Geog courses. But it doesn't matter much because most Geography degrees start general and then they choose modules to match their interests.