The correct answer is C. flex-grow.
Flex-grow is a CSS property that specifies how much the item will grow relative to the rest of the flexible items inside the same container. The value of flex-grow can be a number between 0 and 1, or it can be a keyword value.
If the value of flex-grow is a number, then the item will grow by that amount relative to the other flexible items. For example, if an item has a flex-grow value of 2, and the other flexible items have flex-grow values of 1, then the item with the flex-grow value of 2 will grow twice as much as the other items.
If the value of flex-grow is a keyword value, then the item will grow according to the following rules:
- auto: The item will grow automatically, based on the available space in the container.
- min-content: The item will grow to a minimum size, which is determined by the content of the item.
- max-content: The item will grow to a maximum size, which is determined by the content of the item.
- initial: The item will grow to its initial size, which is the size it had before the flex container was created.
- inherit: The item will inherit the flex-grow value of its parent element.
Flex-grow is one of the four main flex properties, along with flex-basis, flex-shrink, and flex-basis. These properties are used to control the size and position of flexible items inside a flex container.