Physics · JEE | Ray Optics and Optical Instruments

Based on the ray diagram of a compound microscope shown in the text, what is the expression for the linear magnification \( m_o \) due to the objective lens in terms of image size \( h' \), object size \( h \), tube length \( L \), and objective focal length \( f_o \)?

1. A
   \( m_o = \frac{h'}{h} = 1 + \frac{D}{f_e} \)
2. B
   \( m_o = \frac{h'}{h} = \frac{f_o}{L} \)
3. C
   \( m_o = \frac{h'}{h} = \frac{D}{f_e} \)
4. D
   \( m_o = \frac{h'}{h} = \frac{L}{f_o} \)