A、Waxes. B、Colors. C、Thicker oil. D、Thinner oil. CWhat ingredient in lipstick can make it last long?

Lipstick plays an important role in sexual attraction and call even protect the lips from drying out in harsh weather: No wonder it’s the most important item in a woman’s personal bag. Around 50 percent of all women wear lipstick. Coloring the lips is certainly not a new idea. Evidence suggests it was practiced as early as 3,500 B.C. In the past, a natural dye was used to paint lips. It was not until the 17th century that lipstick manufacturing really took off. The lip- stick was made of mixtures that included pig fat. It was kept in tiny pots and applied with a coloring stick.
    Lipstick was invented and first shown by Parisian merchants in Amsterdam. But these "little red sausages" were less than practical. They were wrapped in silk paper and the ends had to be broken off before each use. They also did not come cheap. Over the years the sticks became less expensive and new colors were developed. But it was not until 1950 that lipstick accidentally was re-invented—this time by the Americans. Today there are so many types of lipsticks and shades that it is hard to keep track of them. Faced with the large number of choices, it is easy to forget that there is a whole science to manufacturing them.
    The basic ingredients are colors, oils and waxes. But they can contain up to 30 different materials. Lipstick manufacturers have to achieve a delicate balance. They need a thicker oil to make the lipstick last longer, but a thinner one to make it easy to apply. Different oils also provide protection for sensitive lips, preventing them from drying up.