First, we are going to find if the function is odd or even. Remember that we can determine if a function is odd of even from its graph by looking at its ends; if both ends go to the same the direction, the function is even. If both ends go to opposite directions, the function is odd. At both ends, the graph of our function go towards the same direction, minus infinity, so we can conclude that our function is even.
Next, we are going to find the possible degree of our function. Remember that the possible degree of a function is the number of x-intercepts.
We can infer from our graph that the function intercepts the x-axis at least 6 times.
We can conclude that the correct answer is: even degrees of 6 or greater.