[单选题]
A student constructs an astronon g2 n9tet ;0c9s y6bif5ld3kkmical telescope wimp-e(nk26l f-gb:zbj th a magnification of 10. If the telescope has a converging lens of focal length 50 cm, what is the resultizlm e -b(-b k2g6f:jpnng length of the telescope?
A. $53 \; cm$
B. $55 \; cm$
C. $60 \; cm$
D. $75 \; cm$
