\[{{\sigma }_{1}}\] and \[{{\sigma }_{2}}\] are the electrical conductivities of Ge and Na respectively. If these substances are heated, then

\[{{\sigma }_{1}}\] decreases and \[{{\sigma }_{2}}\] increases

Both \[{{\sigma }_{1}}\] and \[{{\sigma }_{2}}\] increase

\[{{\sigma }_{1}}\] increases and \[{{\sigma }_{2}}\] decreases

Both \[{{\sigma }_{1}}\] and \[{{\sigma }_{2}}\] decrease

\[{{\sigma }_{1}}\] and \[{{\sigma }_{2}}\] are the electrical conduct

1.	\[{{\sigma }_{1}}\] and \[{{\sigma }_{2}}\] are the electrical conductivities of Ge and Na respectively. If these substances are heated, then
A.	Both \[{{\sigma }_{1}}\] and \[{{\sigma }_{2}}\] increase
B.	\[{{\sigma }_{1}}\] increases and \[{{\sigma }_{2}}\] decreases
C.	\[{{\sigma }_{1}}\] decreases and \[{{\sigma }_{2}}\] increases
D.	Both \[{{\sigma }_{1}}\] and \[{{\sigma }_{2}}\] decrease
Answer» C. \[{{\sigma }_{1}}\] decreases and \[{{\sigma }_{2}}\] increases