German silver does not contain

Read the following statements :
$(I)$ $Al$ has greater affinity than that of $Cr$ for oxygen
$(II)$ $Al$ can be used for reduction of $Fe_2O_3$
$(III)$ Carbon is used for reduction of $PbO$
$(IV)$ $SnO_2$ can be reduced by carbon
Choose the correct set of statement$(s)$:

The reaction that does $NOT$ take place in a blast furnace between $900 \ K$ to $1500 \ K$ temperature range during the extraction of iron is:

Which of the following processes is $NOT$ involved in the extraction of metal from cassiterite $(SnO_2)$ ore?

Which alloy contains a non-metal?

Among the following compounds,the number of those present in copper matte is $......$
$A.$ $CuCO_3$
$B.$ $Cu_2S$
$C.$ $Cu_2O$
$D.$ $FeO$