What is the answer to this probably dumb question some interviewers keep asking in interviews.

The question I keep getting is

" How do you load balance(non blocking ) true load balancing inbound internet routes on your internet routers with bgp"

I said maybe get the ISP to agree to match multipaths at equal cost with them still not likely to work.

What's the proper answer Some said med others said as prepend. I know those dont "load balance"

Why are they asking these questions.