Critical Reasoning (CR) | Re: In emerging economies in Africa and other regions, large foreign banks

I am a little confused about the 1 st premise that talks about the colonial banks. What's its purpose? If the answer is B, then couldn't the argument just be:

The development of African countries' economies requires financing of the small businesses that dominate their manufacturing, farming, and services sectors. So economic growth will be likely to occur if local banks take on this portion of the financial services markets, since __________.

Option B is something that we could have stated even
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