Which statement about trees is false?
a. each node in a tree contains two links.
b. the children of a node are called siblings.
c. a node with no children is called a leaf node.
d. a tree is a nonlinear, two-dimensional data structure.

The correct answer is A.

Explanation:

B is true if the two nodes are descending from the same parent node, they are called sibling nodes.

C is true, the nodes which do not have any nodes branching from them are called leaf nodes and mark the end of that specific branch.

D is true, a node tree is defined as nonlinear set of nodes growing downwards which are linked together.

The false option is A, a node in a node tree does not have to contain at least two links, it can be a leaf node.

I hope this answer helps.