[单选题]
A student constructs an astronomical telescope with a magniou/ 7 zydhe;h. :z1pyufication of 1 .i,umwc2 o1ftyee *v/z+aph10. If the telescope has a converging lens of foct/ h2,eum1*.1ypwzoce f+avial length 50 cm, what is the resulting length of the telescope?
A. $53 \; cm$
B. $55 \; cm$
C. $60 \; cm$
D. $75 \; cm$
