What Is the Actus Reus of an Attempt

What is the actus reus of an attempt?

A) that the defendant has done an act which is more than merely preparatory to the commission of the offence
B) that the defendant has tried, but failed to commit the offence and the victim has suffered no harm
C) that the defendant has done more than merely thinking about committing the offence, but has put his plan into practice
D) that the defendant has encouraged others to help him commit an offence