Read the given statements and conclusions carefully. Assuming that the information given in the statements is true, even if it appears to be at variance with commonly known facts, decide which of the given conclusions logically follow(s) from the statements.
Statements:
No introvert is an extrovert.
All extroverts are ambiverts.
Conclusions:
I. No introvert is an ambivert.
II. No ambivert is an introvert.
III. Some ambiverts are extroverts.
IV. All ambiverts are extroverts.