Concept:Wood used for electric poles must be strong, straight, and highly resistant to termites, moisture, and decay.
Explanation:Electric poles are exposed to harsh outdoor weather and must support heavy electric cables safely.
Therefore, the wood selected should be durable and able to last for many years without rotting or bending.
Teak is a dense hardwood that contains natural oils, making it highly resistant to termites, fungi, and moisture damage.
It also has a straight grain and excellent mechanical strength, which are essential qualities for bearing the weight of electric wires.
In contrast, Indian almond and silk cotton trees produce soft, lightweight wood that breaks easily under stress.
Mango wood is moderately strong, but it does not offer the same long-term durability as teak when kept outdoors.
So, among all the listed options, teak is the only tree species that fulfills the strength and durability requirements for making electric poles.
Answer:D. teak