[单选题]
A student constructs anop/i6kn gn.zw-, pgl * astronomical telescope with si rke 1).9hmga magnification of 10. If the telescope has a converging lens of focal length 50 cm9.r)h mg i1esk, what is the resulting length of the telescope?
A. $53 \; cm$
B. $55 \; cm$
C. $60 \; cm$
D. $75 \; cm$
