Nuclei of a radioactive element `X` are being produced at a constant rate `K` and this element decays to a stable nucleus `Y` with a decay constant `lambda` and half-life `T_(1//3)`. At the time `t=0`, there are `N_(0) `nuclei of the element X.
The number `N_(Y)` of nuclei of `Y` at time `t` is .
A. `qt-((q-lambdaN_(0))/(lambda))e^(-lambda t)+(q-lambdaN_(0))/(lambda)`
B. `qt+((q-lambdaN_(0))/(lambda))e^(-lambda t)`
C. `qt+((q-lambdaN_(0))/(lambda))e^(-lambda t)+(1-lambdaN)/(lambda)`
D. `qt-((q-lambdaN_(0))/(lambda))e^(-lambda t)`