There aren´t any ABCD options so how about a brief explanation.
A dependent variable is a person, place, or thing that relies on another person, place, or thing for change. In a flower patch, the bee is the independent variable. It can carry whatever pollen without fail. The flowers are at the mercy of the bee whether they receive pollen or not, cypress pollen or sunflower pollen. Therefore, the flower(s) are the dependent variable(s).