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Explanation:

Step1: Recall cosine - function properties

The general form of a cosine function is $y = A\cos(Bx - C)+D$. For the function $y=-3\cos(3x)$, we have $A = - 3$, $B = 3$, $C = 0$, and $D = 0$.

Step2: Determine the amplitude

The amplitude of the function $y = A\cos(Bx)$ is given by $|A|$. Here, $|A|=| - 3|=3$, so the graph oscillates between $y = 3$ and $y=-3$.

Step3: Determine the period

The period of the function $y=\cos(Bx)$ is $T=\frac{2\pi}{|B|}$. For $y=-3\cos(3x)$, $B = 3$, so the period $T=\frac{2\pi}{3}$.

Step4: Analyze the negative sign

The negative sign in front of the cosine function reflects the graph of $y = 3\cos(3x)$ about the $x -$axis. When $x = 0$, $y=-3\cos(0)=-3$.

Answer:

The graph that has an amplitude of 3 (oscillates between $y = 3$ and $y=-3$), a period of $\frac{2\pi}{3}$, and starts at the point $(0, - 3)$ (since when $x = 0$, $y=-3$) is the correct graph. Without seeing the specific options clearly labeled, based on these properties, you should be able to identify the correct graph among the choices.