For the digital circuit shown in figure, the output Q3Q2Q1Q0

For the digital circuit shown in figure, the output Q₃Q₂Q₁Q₀ = 0001 initially. After a clock pulse appear, the output Q₃Q₂Q₁Q₀ will be

When the clock pulse arrives,
J₀ = 0,     so Q_n+1 = Q_n
K₀ = 0      or Q₀ will remain 1
J₁ = K = 1      so Q₁ will become Q₁ or 1