Use the Figure Above to Answer the Corresponding Questions

Short Answer

Use the figure above to answer the corresponding questions.
The structure labeled "1"
$\begin{array}{ll}\text { a. } & \text { is a microfilament } \\\text { b. } & \text { is made of actin } \\\text { c. } & \text { originates at a centriole }\\d.&\text { is a "highway" for myosin motor molecules }\\e.&\text { all of these }\\\end{array}$