The correct option is B Scapegoat
A scapegoat is a person who is blamed for the wrongdoings, mistakes, or faults of others, especially for reasons of expediency. For example, "few things are harder for kids to bear than being scapegoated". Hence, Option B is correct. Among the rest of the options, innocent means not guilty of a crime or offence, ignoramus means an ignorant or stupid person, nincompoop means a foolish or stupid person. These do not express the intended meaning, hence incorrect.