Among the following statements,the incorrect one is:

What type of circulatory system is present in humans?

The bacteria increases at a rate proportional to the number of bacteria present. If the original number $N$ doubles in $4 \text{ hours}$,then the number of bacteria in $12 \text{ hours}$ will be (in $N$)

The Effective Atomic Number $(EAN)$ of $Co(CO)_4$ is $35$,hence it is less stable. It attains stability by:

If $\cos \theta - 4 \sin \theta = 1$,then $\sin \theta + 4 \cos \theta$ is equal to

The $PV$ diagram shows four different possible reversible processes performed on a monatomic ideal gas. Process $A$ is isobaric (constant pressure). Process $B$ is isothermal (constant temperature). Process $C$ is adiabatic. Process $D$ is isochoric (constant volume). For which process(es) does the temperature of the gas decrease?