What is the output of the margin value when used within this context, assuming that its containing element is larger than 800px?

.example {
width: 800px;
margin: 0 auto;
}

• The example element will have 0 margin space around the whole element. The auto value will center align the element horizontally and vertically within its container.
• The example element will have 0 margin space on the left and right. It will be sized automatically on the top and bottom, which will center align the element within its container.
• The example element will have 0 margin space on the top and bottom. The margin will be sized automatically on the left and right, which may center align the element within its container.
• The margin value is invalid because its missing a unit measurement after the 0.