，对不起？ answer is volcanism
Explanation:
Ans. B
* I am not sure about this answer, if I am wrong pls correct my mistake.
Answer:
The right answer is intercalated discs.
Explanation:
If you observe cardiac muscles under a microscope, the first feature that appears is Intercalated discs. Cardiac muscles contains heart muscle cells which are called as cardiomyocytes which are linked by these discs to perform a single functional organ.
Intercalated discs helps in harmonizing the contraction of cardiac tissues.
(2) They stimulate uncontrolled cell division is your answer. This causes cancer, specifically for lungs, lung cancer.
