Find the run-on, if no run-on choose A
Graphite is a form of carbon used in pencils. It's greasy and soft with a metallic luster, making it an ideal writing material.
A. This sentence is not a run-on.
B. Graphite is a form of carbon used in pencils it's greasy and soft with a metallic luster, making it an ideal writing material.
C. Graphite is a form of carbon used in pencils, notably, it's greasy and soft with a metallic luster, making it an ideal writing material.
D. Graphite is a form of carbon used in pencils, it's greasy and soft with a metallic luster, making it an ideal writing material.
