The amount of cesium- 137 remaining after x years in an initial sample of 200 milligrams can be found using the equation C(x)=200 e⁻⁰.⁰⁰²²⁹⁵ . In approximately how many years will the sample contain 120 milligrams of cesium-137?
A. 13
B. 22
C. 26
D. 39