Cardiac muscle fibres are

Mainly,skeletal muscles are named on the basis of:

The sliding filament theory can be best explained as:

What is the dark line lying in the middle of the $H$-zone called?

Based on their location in the human body or animals,the types of muscles are:
$I.$ Skeletal
$II.$ Visceral
$III.$ Cardiac
$IV.$ Non-visceral
The correct option is:

Striated muscle fibers are found in......