Answer:
Option C is correct that is none of the above.
Explanation:
Height of the mango tree = 2.6 meters.
Depth up to which roots of mango tree extend =

We need to find expressions that represent the difference in elevation between the top of the mango tree and the tips of its roots
⇒ we need to find the distance between top of the mango and tip of the tree.
Distance = Distance between ground & top of tree + distance between ground & tip of root
Therefore, Option C is correct that is none of the above.