**Core Concept**
Z-lines are specialized structures within the sarcomere that serve as attachment points for actin filaments and other components of the muscle cytoskeleton. The anchorage of Z-lines to the sarcolemma is crucial for maintaining the structural integrity and function of skeletal muscle.

**Why the Correct Answer is Right**
The correct answer is based on the understanding of the muscle cell membrane, known as the sarcolemma, and its interaction with the Z-disk. The sarcolemma envelops the entire muscle fiber, while the Z-disk is a dense region that anchors the actin filaments and provides a site for force transmission. The M-line, located between the A and I bands, is also involved in force transmission but does not directly anchor the Z-line to the sarcolemma. Instead, the Z-line is linked to the sarcolemma through a complex network of proteins and structures, including the costameres.

**Why Each Wrong Option is Incorrect**
* **Option A:** This is not a recognized structure or mechanism for anchoring Z-lines to the sarcolemma.
* **Option B:** While the M-line is involved in force transmission, it does not directly anchor the Z-line to the sarcolemma.
* **Option C:** This is not a correct description of the relationship between Z-lines and the sarcolemma.

**Clinical Pearl / High-Yield Fact**
The costameres, which are involved in anchoring the Z-line to the sarcolemma, are also critical for maintaining the structural integrity of skeletal muscle. Defects in costamere function have been implicated in various muscle disorders, such as Duchenne muscular dystrophy.

**Correct Answer: C. Z-lines are anchored to the sarcolemma by costameres.