Answer: cardiac muscle.
- A cardiac muscle
- B skeletal muscle
- C smooth muscle
- D voluntary muscle
Correct answer: A. cardiac muscle
Explanation: Cardiac muscle is striated, involuntary and found only in the heart.

A sarcomere (Z line to Z line): during contraction the I band and H zone shorten as thin filaments slide over thick, while the A band stays the same length. Image: SlothMcCarty, CC BY-SA 3.0, via Wikimedia Commons.
Concept context
Types of movement, muscle contraction, skeletal system, joints, and disorders. Important for Class 11 and NEET.