If we consider Boyles law for gases, it states the following equation,
PV/T =k
where k is a constant
P-pressure, T- temperature and V -volume
the volume is constant at both situations as its a rigid tank as mentioned in the questions.
Therefore we consider Volume to be constant , then equation is
P/T = kV
kV = c (new constant)
P/T = c
P = cT
Therefore pressure is inversely proportional to temperature, whatever change in pressure would cause the same kind of change in temperature as well.
therefore when T decreases, P also decreases.
Answer is B