A solenoid valve used in a refrigeration system should be installed （）.
A. with the axis of the solenoid horizontal, sensing temperature of the box, and upstream of the thermal expansion valve
B. upright, sensing temperature of the box, and upstream of the thermal expansion valve
C. upright, sensing temperature of the box, and downstream of the thermal expansion valve
D. upright, sensing heat of the tail coil, and upstream of the thermal expansion valve
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