'Due to', 'owing to' and 'because of'
To start off, allow me to consider an issue that has been argued over for centuries, but is less widely thought about now. 'Due to', 'owing to', and 'because of' are now widely considered interchangeable, but it wasn't always this way. 'Due' and 'owing' are adjectives rather than conjunctions, so grammarians were displeased when, at around the turn of the nineteenth century, 'owing to' was coming into common usage, and again about a century later when the same thing happened to 'due to'. However, most now argue that they are now so common that they must be considered as correct as the (definitely correct) 'because of'. There is no hard-and-fast rule as to what to use, but remember to be consistent. Use all of them or just 'because of', and stick to that. Personally, for stylistic reasons, I just use 'because of'.