Explanation:

Let's break down each statement:

- I. The physical aspect of crime is actus reus.

Correct. "Actus reus" refers to the actual criminal act, which is the physical element.

- II. The mental aspect of crime is mens rea.

Correct. "Mens rea" means having a guilty mind or intent, which is the mental element.

- III. The motive is the desire to commit crime.

Not entirely correct. Motive is the reason behind committing a crime, not simply the "desire" to commit it. Motive explains why a person might want to commit a crime, but it's not necessary for proving the crime.

Let's analyze the options:

- Option 1: I & II are correct but III is not correct

This matches the explanation above.

- Option 2: only II & III

Incorrect. Statement III is not completely correct, and leaving out I is not justified.

- Option 3: only II & III

Same as above.

- Option 4: all the above

Incorrect, since statement III isn't fully correct.

Correct answer: Option 1: I & II are correct but III is not correct.