Answer:
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.