# Parasympathetic stimulation of heart causes______________? with Answer - Physiology Mcqs | ExamZone

> Solved MCQ: Parasympathetic stimulation of heart causes______________? Correct Answer: A. SA node decreases firing. Verified answer explanation for FPSC, PPSC, MDCAT, NTS, and CSS competitive exam preparation.

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# Parasympathetic stimulation of heart causes______________?

Direct Answer & Quick Reference

The correct option is **A. SA node decreases firing**.

A. SA node decreases firing **(Correct Answer)**

B. Increased AV node excitability

C. Decreased ventricular contraction

D. Tachycardia

Verified Key: A. SA node decreases firing
Solved by 2,102+ students

Verified against official examination board answer keys and standard curriculum textbooks.

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