— How are you getting on with your study?      

— _____, I haven't made _____ I expected. [ ]

A. Well, as much progress as

B. Oh, so much progress as

C. What, as many progress as

D. Yes, so more progress as

当冷热两流体的α相差较大时，欲提高换热器的K值关键是采取措施提高较小α。