Identify the Truthfulness of the Following Statements

Identify the truthfulness of the following statements. III.In perfectly competitive markets there are no externalities.That is,actions of decision-makers on each others' well being do not extend beyond those effects transmitted by prices.
IV.Partial equilibrium analysis determines equilibrium in a single market,taking the prices and outputs of other markets as fixed.

A) Both I and II are true.
B) Both I and II are false.
C) I is true; II is false.
D) I is false; II is true.