The alarm reaction stage refers to the initial symptoms the body experiences when under stress. You may be familiar with the “fight-or-flight” response, which is a physiological response to stress. This natural reaction prepares you to either flee or protect yourself in dangerous situations. Your heart rate increases, your adrenal gland releases cortisol (a stress hormone), and you receive a boost of adrenaline, which increases energy. This fight-or-flight response occurs in the alarm reaction stage.
Since there is no action verb, I am positive that the answer is Predicate Nominative, because there is a linking verb (is) but no action. Direct and Indirect objects require action/