[单选题]
A microscope has an objectguh,eb qh v;8;ive lens of fm hk8ofhje,s u3*z- a+ocal length 1.4 mm and an eyepiece of focal length 20 mm, adjusted for minimum eyestrain. A blood sample is placed 1.5 mm from the objective. What is the oveh+ak8* ,z3-mhe sjuofrall magnification?
