To determine if Huda is achieving a moderate intensity workout according to CDC standards, she should aim for 64% to 76% of her maximum heart rate.
Therefore, the most accurate choice for moderate intensity would be:
when she reaches 77 percent of her maximum heart rate.
However, if you consider moderate intensity specifically, the right choice is:
when she reaches 64 percent of her maximum heart rate.
Since the question asks for the option that indicates moderate intensity, the most likely correct answer is:
when she reaches 64 percent of her maximum heart rate.