What is the definition of the object of study in criminology according to the text?

The object of study in criminology is defined in strictly legal terms.
Some criminological schools are trying to replace legal-normative definitions with sociological ones.
The acceptance of specific categories of 'crime' and 'criminal' according to legislation invalidates theoretical criminological research from a scientific point of view.
The data on criminal law and crime and criminals statistics are the only valid sources for criminological research.
a) I and III are correct.
b) II and IV are correct.
c) I, II, and III are correct.
d) II and III are correct.