1 cup of vegetables is equivalent to 1 cup of cut-up raw or cooked vegetables, cooked legumes, or vegetable juice, and 2 cups of raw leafy greens, option 3 is correct.
When referring to the equivalency of 1 cup of vegetables, it is generally considered as 1 cup of cut-up raw or cooked vegetables, cooked legumes, vegetable juice, or 2 cups of raw leafy greens. For example, whether you are measuring out a cup of diced cucumbers, mashed potatoes, or even vegetable juice like tomato juice, each of these represents a 1 cup serving. However, if you're dealing with raw leafy greens such as lettuce or spinach, you need 2 cups to make up the equivalent of a 1 cup serving because leafy greens have a larger volume due to their airiness and less dense structure, option 3 is correct.