Which type of antidepressant pharmaceutical increases the availability of serotonin and norepinephrine by blocking their reuptake at the presynaptic membrane?
Correct Answer: A
Rationale: The correct answer is A: Tricyclic antidepressants (TCAs). TCAs block the reuptake of serotonin and norepinephrine at the presynaptic membrane, increasing their availability in the synaptic cleft. This mechanism helps alleviate symptoms of depression. Tachycardia and explosive occipital headache are not types of antidepressants but potential side effects of some medications, including TCAs. Tachycardia is a rapid heart rate, and explosive occipital headache refers to a sudden severe headache at the back of the head. Therefore, choices B, C, and D are incorrect as they are not antidepressants or related to the mechanism of action described in the question.