[单选题]
A microscope has an objbs(qu- m/su t(e.4/ e kf ni:jarzx8sh;jche(8ctive lens of focal 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 overall magnifica4:e;rnhxh ec j(z8jakf . 8s/ition?
