The correct answer is option 2, climbers. Climbers are a type of plant that have weak stems and rely on neighbouring structures for support to climb upwards. This is an adaptation that allows them to reach for sunlight, as climbing helps them access higher levels. Unlike shrubs, climbers do not have strong, self-supporting stems. Shrubs, option 1, have woody stems and are generally able to stand upright on their own. Trees, option 3, also have strong trunks and branches that allow them to grow tall without the need for support. Herbs, option 4, are smaller plants that do not have woody stems and typically do not climb or rely on nearby structures for support.