Phototropism is a plant's growth response to: Gravity Light Water Touch

## Step 1<br />Phototropism is a biological phenomenon where plants grow or orient themselves in response to light. This is a survival mechanism that allows plants to maximize their exposure to sunlight, which is essential for photosynthesis.<br /><br />## Step 2<br />The other options provided, such as gravity, water, and touch, are also factors that can influence plant growth. However, they are not the primary cause of phototropism.<br /><br />## Step 3<br />Gravity influences plant growth through a process called gravitropism or geotropism. This is the growth of plants in response to gravity.<br /><br />## Step 4<br />Water influences plant growth through a process called hydrotropism. This is the growth of plants in response to water.<br /><br />## Step 5<br />Touch influences plant growth through a process called thigmotropism. This is the growth of plants in response to touch.