I think it’s purposefully broad and vague. I read it as a property development or construction/planning project that is or has happened recently. The Battersea Power Station development springs to mind.
I’d go about it like this: first, have a think about what interests you. This could be anything from your hobbies to particular law firm practice areas you’re interested in. Starting here is important as they want to know why it interests you - this is what helps you stand out from the crowd. ➡️ With an idea of what interests you, see what’s happening in London in connection to that. For example, maybe you’re interested in renewable energy, and there’s a construction project in London designed to install X amount of EV charging points by the end of 2022. ➡️ With an idea in mind, you can now explain why it interests you. Maybe you did a course on renewable energy and liked how it combined new technology and problem solving ➡️ then tie your question into how the firm can assist. I remember WBD has a strong energy sector focus, so there’s lots of knowledge they can support with on a project around clean energy. For example, construction, development, planning advice.
Hope this helps!