I cannot give you a background for this specific carrier and photo. But atleast from a technological perspective, I can answer your question:
It is a "Carrier, Bren No.2" best recognizable from the sloped rear part and a single passenger comparment. It is one of the many versions of the Universal carrier family before they became "universal". This means before individual designs for specific purpose (Bren Gun Carrier, Machine gun carrier, Scout carrier, armored recognaissance, AT variants, and so forth) were all dropped in favor of the single "universal" carrier production model, we all know very well.
Below you see a top view of the Carrier, Bren No.2 showing the single passenger compartment.