I`m guessing its in health and social care and a diploma question?

Unsafe practice that puts your service user at risk could range from Infection control, food storage, protecting confidentiality or not carrying out the agreed tasks to a standard that caters to the individuals needs and personal preferences. 

But the most obvious answer is Not carrying out moving and handling correctly. Waste disposing, Administering medication in the wrong way. Things that could cause harm to your service user.