The common ratio is the constant factor between consecutive terms of a geometric sequence.
It can be obtained using the formula below
[tex]r=\frac{T_2}{T_1}\text{ =}\frac{T_3}{T_2}[/tex]
Where r = common ration, T1 is the first term, T2 = second term and T3 = third term
From the sequence given,
T1 = 0.1
T2 = 0.01
T3= 0.001
Substituting the value in the above equation
[tex]r=\frac{0.01}{0.1}=\frac{0.001}{0.01}=\text{ 0.1}[/tex]
Hence the common ratio, r = 0.1
option C is correct
