context: Lemons are citrus fruits (Citrus aurantiifolia), a family tree of citrus (Rutaceae). Its shape is oval to yellow, with a diameter of 3-6 cm. They have a sour taste because of the acidity in them. Lemons are often used to add flavor to food and drink. It is usually smaller than a lemon, and a good source of vitamin C. In tropical and subtropical zones the plants can grow throughout the year as long as water is available. Lemons are less bitter than lemons.
question: In what family of lemons does the lemon belong?
answers.text: citrus