GKFix MCQ Question

In the context of a telescope, what do the symbols fₒ and fₑ usually represent?

• A. fₒ: Focal length of the eyepiece; fₑ: Focal length of the objective.
• B. fₒ: Diameter of the objective; fₑ: Diameter of the eyepiece.
• C. fₒ: Focal length of the objective; fₑ: Focal length of the eyepiece.
• D. fₒ: Length of the telescope; fₑ: Length of the eyepiece tube.