Explain the Functional Significance of the T-Tubules of the Sarcolemma

Explain the functional significance of the T-tubules of the sarcolemma and the terminal cisternae of the sarcoplasmic reticulum.

A) The increased surface of both structures increases the speed and efficiency with which the end-plate potential leads to sarcomere contraction.
B) The abundance of each structure increases the rate of ATP production.
C) The T-tubules and terminal cisternae enhance the chemical attraction between myosin and actin.
D) The increased surface area provides space for more ligand gated ion channels, thus increasing the effectiveness of acetylcholine binding.