How do thorns contribute to plant survival?

Thorns serve as a crucial adaptation for plants by acting as a physical barrier against herbivores. Many animals, including insects and larger herbivores, may be deterred from feeding on plants that have thorns due to the injury risk associated with piercing spines or sharp edges. This defensive mechanism reduces the likelihood of being consumed, thereby increasing the plant's chances of survival and reproductive success.

In contrast, the other options do not accurately represent the role of thorns. For example, thorns do not promote photosynthesis or increase attractiveness to pollinators; their primary function is protective rather than functional in photosynthesis or pollination. Additionally, while nutrient uptake is vital for plant health, thorns do not facilitate this process directly. Instead, they deter herbivory, allowing plants to allocate more resources to growth and reproduction instead of recovery from feeding damage.