I would say the best advice would be to start with BBC Business on their website. You're applying for consulting and therefore you just need a basic and broad understanding of business and what is currently happening in the business world. I would make the BBC Business page your homepage on your laptop and be sure to read somewhere between 3 and 5 articles a day off the website. You'll soon gain some insight into what is happening in the business world and you'll be able to talk about a few themes with specific companies or industries.
In regards to interview questions for commercial awareness, the most frequent will be something along the lines of 'tell me about a recent business story you found interesting', followed by follow on questions depending on what you answer with. For this, you just need to show that you've read something interesting and formed an opinion on it, how the companies/industries in question are affected by the story and how they could react to it, to best position themselves etc. You may be asked something more specific, but if so then it is likely to be something that you should really know about, and so it would definitely be covered on a major news service like the BBC.
Once you've built up a good grounding, then perhaps something like Bloomberg or Reuters would offer more insight into various stories. For now, BBC should be fine, and to be honest, the former two are more on the financial side.