Which of the following is preorder processing for a binary tree?

a.
i) process the right subtree
ii) process the root node data
iii) process the left subtree
b.
i) process the left subtree
ii) process the root node data
iii) process the right subtree
c.
i) process the root node data
ii) process the left subtree
iii) process the right subtree
d.
i) process the left subtree
ii) process the right subtree
iii) process the root node
e.
i) process the right subtree
ii) process the left subtree
iii) process the root node

c)
Explanation: Part b) is in order. Part d) is post order.