In the studies of Joffe and Sperll, it was observed that ________ is efficient for solubilizing Ni but the presence of ______ had adverse effect on leaching.

In the studies of Joffe and Sperll, it was observed that ________ is

1.	In the studies of Joffe and Sperll, it was observed that ________ is efficient for solubilizing Ni but the presence of ______ had adverse effect on leaching.
A.	T. ferrooxidans; cobalt
B.	T.trioxidanes; molybdenum
C.	T. ferrooxidans; molybdenum
D.	T. trioxidanes; cobalt
Answer» D. T. trioxidanes; cobalt