单选题The phraseheat recoveryrefers to a _____.Amethod of concealing the source of heatBspecial form of air-conditioningCsupplementary hot water systemDway of reclaiming and re-using heat
单选题
The phraseheat recoveryrefers to a _____.
A
method of concealing the source of heat
B
special form of air-conditioning
C
supplementary hot water system
D
way of reclaiming and re-using heat
参考解析
解析：